Merge changes I475d55b3,I2bc7b3f7,Ibc04347f,I17368493,I642953e4, ... * changes: Use Java record for Forwarder.Result Add metric displaying the number of retries required to forward event Add metrics to measure time of processing forwarded event Add metric reporting the success/failure of event processing Add metrics measuring time between event creation and response Use millisecond accuracy for IndexEvent.eventCreatedOn Add metric about failure/success count of forwarding request Use enum for Command.TYPE

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/EventType.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/EventType.java
new file mode 100644
index 0000000..8cfea0c
--- /dev/null
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/EventType.java

@@ -0,0 +1,29 @@
+// Copyright (C) 2025 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.ericsson.gerrit.plugins.highavailability.forwarder;
+
+public enum EventType {
+  CACHE_EVICTION,
+  EVENT_SENT,
+  INDEX_ACCOUNT_UPDATE,
+  INDEX_CHANGE_DELETION,
+  INDEX_CHANGE_DELETION_ALL_OF_PROJECT,
+  INDEX_CHANGE_UPDATE,
+  INDEX_CHANGE_UPDATE_BATCH,
+  INDEX_GROUP_UPDATE,
+  INDEX_PROJECT_UPDATE,
+  PROJECT_LIST_ADDITION,
+  PROJECT_LIST_DELETION
+}

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexAccountHandler.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexAccountHandler.java
index b2f8141..bee5f2e 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexAccountHandler.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexAccountHandler.java

@@ -38,8 +38,13 @@
 
   @Override
   protected CompletableFuture<Boolean> doIndex(Account.Id id, Optional<IndexEvent> indexEvent) {
-    indexer.index(id);
-    log.atFine().log("Account %s successfully indexed", id);
+    try {
+      indexer.index(id);
+      log.atFine().log("Account %s successfully indexed", id);
+    } catch (RuntimeException e) {
+      log.atFine().log("Account %s failed to be indexed", id);
+      throw e;
+    }
     return CompletableFuture.completedFuture(true);
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexChangeHandler.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexChangeHandler.java
index fd654ba..80aa836 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexChangeHandler.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexChangeHandler.java

@@ -68,7 +68,8 @@
         () -> {
           try (ManualRequestContext ctx = oneOffCtx.open()) {
             Context.setForwardedEvent(true);
-            return indexOnce(id, indexEvent);
+            boolean result = indexOnce(id, indexEvent);
+            return result;
           }
         });
   }
@@ -123,11 +124,22 @@
       throws IOException {
     if (ALL_CHANGES_FOR_PROJECT.equals(extractChangeId(id))) {
       Project.NameKey projectName = parseProject(id);
-      indexer.deleteAllForProject(projectName);
-      log.atFine().log("All %s changes successfully deleted from index", projectName.get());
+      try {
+        indexer.deleteAllForProject(projectName);
+        log.atFine().log("All %s changes successfully deleted from index", projectName.get());
+      } catch (RuntimeException e) {
+        log.atFine().log(
+            "An error occured during deletion of all %s changes from index", projectName.get());
+        throw e;
+      }
     } else {
-      indexer.delete(parseChangeId(id));
-      log.atFine().log("Change %s successfully deleted from index", id);
+      try {
+        indexer.delete(parseChangeId(id));
+        log.atFine().log("Change %s successfully deleted from index", id);
+      } catch (RuntimeException e) {
+        log.atFine().log("Change %s could not be deleted from index", id);
+        throw e;
+      }
     }
     return CompletableFuture.completedFuture(true);
   }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexGroupHandler.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexGroupHandler.java
index 99ac369..01f8680 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexGroupHandler.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwardedIndexGroupHandler.java

@@ -39,8 +39,13 @@
   @Override
   protected CompletableFuture<Boolean> doIndex(
       AccountGroup.UUID uuid, Optional<IndexEvent> indexEvent) {
-    indexer.index(uuid);
-    log.atFine().log("Group %s successfully indexed", uuid);
+    try {
+      indexer.index(uuid);
+      log.atFine().log("Group %s successfully indexed", uuid);
+    } catch (RuntimeException e) {
+      log.atFine().log("Group %s could not be indexed", uuid);
+      throw e;
+    }
     return CompletableFuture.completedFuture(true);
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/Forwarder.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/Forwarder.java
index 3854ee3..3bf08b4 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/Forwarder.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/Forwarder.java

@@ -21,6 +21,12 @@
 /** Forward indexing, stream events and cache evictions to the other primary */
 public interface Forwarder {
 
+  public record Result(EventType type, boolean result, boolean isRecoverable) {
+    public Result(EventType task, boolean result) {
+      this(task, result, true);
+    }
+  }
+
   /**
    * Forward an account indexing event to the other primary.
    *
@@ -29,7 +35,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> indexAccount(int accountId, IndexEvent indexEvent);
+  CompletableFuture<Result> indexAccount(int accountId, IndexEvent indexEvent);
 
   /**
    * Forward a change indexing event to the other primary.
@@ -40,7 +46,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> indexChange(String projectName, int changeId, IndexEvent indexEvent);
+  CompletableFuture<Result> indexChange(String projectName, int changeId, IndexEvent indexEvent);
 
   /**
    * Forward a change indexing event to the other primary using batch index endpoint.
@@ -51,7 +57,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> batchIndexChange(
+  CompletableFuture<Result> batchIndexChange(
       String projectName, int changeId, IndexEvent indexEvent);
 
   /**
@@ -62,7 +68,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> deleteChangeFromIndex(int changeId, IndexEvent indexEvent);
+  CompletableFuture<Result> deleteChangeFromIndex(int changeId, IndexEvent indexEvent);
 
   /**
    * Forward a group indexing event to the other primary.
@@ -72,7 +78,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> indexGroup(String uuid, IndexEvent indexEvent);
+  CompletableFuture<Result> indexGroup(String uuid, IndexEvent indexEvent);
 
   /**
    * Forward a project indexing event to the other primary.
@@ -82,7 +88,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> indexProject(String projectName, IndexEvent indexEvent);
+  CompletableFuture<Result> indexProject(String projectName, IndexEvent indexEvent);
 
   /**
    * Forward a stream event to the other primary.
@@ -91,7 +97,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> send(Event event);
+  CompletableFuture<Result> send(Event event);
 
   /**
    * Forward a cache eviction event to the other primary.
@@ -101,7 +107,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> evict(String cacheName, Object key);
+  CompletableFuture<Result> evict(String cacheName, Object key);
 
   /**
    * Forward an addition to the project list cache to the other primary.
@@ -110,7 +116,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> addToProjectList(String projectName);
+  CompletableFuture<Result> addToProjectList(String projectName);
 
   /**
    * Forward a removal from the project list cache to the other primary.
@@ -119,7 +125,7 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> removeFromProjectList(String projectName);
+  CompletableFuture<Result> removeFromProjectList(String projectName);
 
   /**
    * Forward the removal of all project changes from index to the other primary.
@@ -128,5 +134,5 @@
    * @return {@link CompletableFuture} of true if successful, otherwise {@link CompletableFuture} of
    *     false.
    */
-  CompletableFuture<Boolean> deleteAllChangesForProject(Project.NameKey projectName);
+  CompletableFuture<Result> deleteAllChangesForProject(Project.NameKey projectName);
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderMetrics.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderMetrics.java
new file mode 100644
index 0000000..eecef15
--- /dev/null
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderMetrics.java

@@ -0,0 +1,83 @@
+// Copyright (C) 2025 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.ericsson.gerrit.plugins.highavailability.forwarder;
+
+import com.google.gerrit.metrics.Counter0;
+import com.google.gerrit.metrics.Description;
+import com.google.gerrit.metrics.Histogram0;
+import com.google.gerrit.metrics.MetricMaker;
+import com.google.gerrit.metrics.Timer0;
+import com.google.inject.assistedinject.Assisted;
+import com.google.inject.assistedinject.AssistedInject;
+import java.util.Locale;
+import java.util.concurrent.TimeUnit;
+
+public class ForwarderMetrics {
+  private final Timer0 latencyMetric;
+  private final Counter0 failureCounterMetric;
+  private final Counter0 successCounterMetric;
+  private final Histogram0 retryMetric;
+
+  public interface Factory {
+    ForwarderMetrics create(EventType eventType);
+  }
+
+  @AssistedInject
+  public ForwarderMetrics(MetricMaker metricMaker, @Assisted EventType eventType) {
+    String event = eventType.toString().toLowerCase(Locale.US);
+
+    this.latencyMetric =
+        metricMaker.newTimer(
+            String.format("forwarding_%s_event/latency", event),
+            new Description(
+                    String.format(
+                        "Time from %s event scheduling to receiving on the other node", event))
+                .setCumulative()
+                .setUnit(Description.Units.MILLISECONDS));
+    this.failureCounterMetric =
+        metricMaker.newCounter(
+            String.format("forwarding_%s_event/failure", event),
+            new Description(String.format("%s events forwarding failures count", event))
+                .setCumulative()
+                .setRate());
+    this.successCounterMetric =
+        metricMaker.newCounter(
+            String.format("forwarding_%s_event/success", event),
+            new Description(String.format("%s events forwarding success count", event))
+                .setCumulative()
+                .setRate());
+    this.retryMetric =
+        metricMaker.newHistogram(
+            String.format("forwarding_%s_event/retries", eventType),
+            new Description(String.format("%s events forwarding retries", eventType))
+                .setCumulative());
+  }
+
+  public void recordResult(boolean isSuccessful) {
+    if (isSuccessful) {
+      successCounterMetric.increment();
+    } else {
+      failureCounterMetric.increment();
+    }
+  }
+
+  public void recordLatency(long latencyMs) {
+    latencyMetric.record(latencyMs, TimeUnit.MILLISECONDS);
+  }
+
+  public void recordRetries(int retries) {
+    retryMetric.record(retries);
+  }
+}

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderMetricsRegistry.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderMetricsRegistry.java
new file mode 100644
index 0000000..97f73f6
--- /dev/null
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderMetricsRegistry.java

@@ -0,0 +1,50 @@
+// Copyright (C) 2025 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.ericsson.gerrit.plugins.highavailability.forwarder;
+
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+
+@Singleton
+public class ForwarderMetricsRegistry {
+
+  private final ForwarderMetrics.Factory metricsFactory;
+
+  private Map<EventType, ForwarderMetrics> metrics = new HashMap<>();
+
+  @Inject
+  public ForwarderMetricsRegistry(ForwarderMetrics.Factory metricsFactory) {
+    this.metricsFactory = metricsFactory;
+    this.putAll(Arrays.asList(EventType.values()));
+  }
+
+  public ForwarderMetrics get(EventType eventType) {
+    return metrics.get(eventType);
+  }
+
+  public void put(EventType task) {
+    metrics.put(task, metricsFactory.create(task));
+  }
+
+  public void putAll(Collection<EventType> eventTypes) {
+    for (EventType eventType : eventTypes) {
+      put(eventType);
+    }
+  }
+}

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderModule.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderModule.java
index 7cb107c..f5c5a39 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderModule.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderModule.java

@@ -15,18 +15,22 @@
 package com.ericsson.gerrit.plugins.highavailability.forwarder;
 
 import com.ericsson.gerrit.plugins.highavailability.ConfigurableAllowedEventListeners;
+import com.google.gerrit.extensions.config.FactoryModule;
 import com.google.gerrit.extensions.registration.DynamicItem;
 import com.google.gerrit.server.events.EventDispatcher;
-import com.google.inject.AbstractModule;
 import com.google.inject.Scopes;
 
-public class ForwarderModule extends AbstractModule {
-
+public class ForwarderModule extends FactoryModule {
   @Override
   protected void configure() {
     bind(AllowedForwardedEventListener.class)
         .to(ConfigurableAllowedEventListeners.class)
         .in(Scopes.SINGLETON);
+    bind(ForwarderMetricsRegistry.class);
     DynamicItem.bind(binder(), EventDispatcher.class).to(ForwardedAwareEventBroker.class);
+    factory(ForwarderMetrics.Factory.class);
+    bind(ForwarderMetricsRegistry.class).in(Scopes.SINGLETON);
+    factory(ProcessorMetrics.Factory.class);
+    bind(ProcessorMetricsRegistry.class).in(Scopes.SINGLETON);
   }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderTask.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderTask.java
new file mode 100644
index 0000000..f8895e1
--- /dev/null
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ForwarderTask.java

@@ -0,0 +1,28 @@
+// Copyright (C) 2025 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.ericsson.gerrit.plugins.highavailability.forwarder;
+
+public enum ForwarderTask {
+  ADD_TO_PROJECTS_LIST,
+  BATCH_INDEX_CHANGE,
+  DELETE_CHANGE_FROM_INDEX,
+  EVICT_CACHE,
+  INDEX_ACCOUNT,
+  INDEX_CHANGE,
+  INDEX_GROUP,
+  INDEX_PROJECT,
+  REMOVE_FROM_PROJECTS_LIST,
+  SEND_EVENT
+}

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/IndexEvent.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/IndexEvent.java
index 71cf044..129af6b 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/IndexEvent.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/IndexEvent.java

@@ -14,12 +14,13 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder;
 
+import java.time.Instant;
 import java.time.LocalDateTime;
 import java.time.ZoneOffset;
 import java.time.format.DateTimeFormatter;
 
 public class IndexEvent {
-  public long eventCreatedOn = System.currentTimeMillis() / 1000;
+  public Instant eventCreatedOn = Instant.now();
   public String targetSha;
   public String metaSha;
 
@@ -31,8 +32,7 @@
         + ((metaSha != null) ? "/meta:" + metaSha : "");
   }
 
-  public static String format(long eventTs) {
-    return LocalDateTime.ofEpochSecond(eventTs, 0, ZoneOffset.UTC)
-        .format(DateTimeFormatter.ISO_DATE_TIME);
+  public static String format(Instant eventTs) {
+    return LocalDateTime.ofInstant(eventTs, ZoneOffset.UTC).format(DateTimeFormatter.ISO_DATE_TIME);
   }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ProcessorMetrics.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ProcessorMetrics.java
new file mode 100644
index 0000000..de1e271
--- /dev/null
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ProcessorMetrics.java

@@ -0,0 +1,94 @@
+// Copyright (C) 2025 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.ericsson.gerrit.plugins.highavailability.forwarder;
+
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.metrics.Counter0;
+import com.google.gerrit.metrics.Description;
+import com.google.gerrit.metrics.MetricMaker;
+import com.google.gerrit.metrics.Timer0;
+import com.google.inject.assistedinject.Assisted;
+import com.google.inject.assistedinject.AssistedInject;
+import java.time.Duration;
+import java.time.Instant;
+import java.util.concurrent.TimeUnit;
+
+public class ProcessorMetrics {
+  private final Timer0 processingTimeMetric;
+  private final Timer0 totalTimeMetric;
+  private final Counter0 failureCounterMetric;
+  private final Counter0 successCounterMetric;
+
+  public interface Factory {
+    ProcessorMetrics create(EventType eventType);
+  }
+
+  @AssistedInject
+  public ProcessorMetrics(MetricMaker metricMaker, @Assisted EventType eventType) {
+    this.processingTimeMetric =
+        metricMaker.newTimer(
+            String.format("forwarded_%s_event_handler/time_processing", eventType),
+            new Description(
+                    String.format(
+                        "Time from receiving an %s event to finish processing it.", eventType))
+                .setCumulative()
+                .setUnit(Description.Units.MILLISECONDS));
+    this.totalTimeMetric =
+        metricMaker.newTimer(
+            String.format("forwarded_%s_event_handler/time_total", eventType),
+            new Description(
+                    String.format(
+                        "Time from %s event scheduling to finish processing it.", eventType))
+                .setCumulative()
+                .setUnit(Description.Units.MILLISECONDS));
+    this.failureCounterMetric =
+        metricMaker.newCounter(
+            String.format("forwarded_%s_event_handler/failure", eventType),
+            new Description(String.format("%s events forwarding failures count", eventType))
+                .setCumulative()
+                .setRate());
+    this.successCounterMetric =
+        metricMaker.newCounter(
+            String.format("forwarded_%s_event_handler/success", eventType),
+            new Description(String.format("%s events forwarding success count", eventType))
+                .setCumulative()
+                .setRate());
+  }
+
+  public void recordResult(boolean isSuccessful) {
+    if (isSuccessful) {
+      successCounterMetric.increment();
+    } else {
+      failureCounterMetric.increment();
+    }
+  }
+
+  public void recordProcessingTime(Long processingTime) {
+    processingTimeMetric.record(processingTime, TimeUnit.MILLISECONDS);
+  }
+
+  public void recordTotalTime(Long totalTime) {
+    totalTimeMetric.record(totalTime, TimeUnit.MILLISECONDS);
+  }
+
+  public void record(@Nullable Instant eventCreatedOn, Instant startTime, boolean success) {
+    Instant now = Instant.now();
+    recordResult(success);
+    recordProcessingTime(Duration.between(startTime, now).toMillis());
+    if (eventCreatedOn != null) {
+      recordTotalTime(Duration.between(eventCreatedOn, now).toMillis());
+    }
+  }
+}

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ProcessorMetricsRegistry.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ProcessorMetricsRegistry.java
new file mode 100644
index 0000000..80504ab
--- /dev/null
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/ProcessorMetricsRegistry.java

@@ -0,0 +1,50 @@
+// Copyright (C) 2025 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.ericsson.gerrit.plugins.highavailability.forwarder;
+
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+
+@Singleton
+public class ProcessorMetricsRegistry {
+
+  private final ProcessorMetrics.Factory metricsFactory;
+
+  private Map<EventType, ProcessorMetrics> metrics = new HashMap<>();
+
+  @Inject
+  public ProcessorMetricsRegistry(ProcessorMetrics.Factory metricsFactory) {
+    this.metricsFactory = metricsFactory;
+    this.putAll(Arrays.asList(EventType.values()));
+  }
+
+  public ProcessorMetrics get(EventType eventType) {
+    return metrics.get(eventType);
+  }
+
+  public void put(EventType task) {
+    metrics.put(task, metricsFactory.create(task));
+  }
+
+  public void putAll(Collection<EventType> eventTypes) {
+    for (EventType eventType : eventTypes) {
+      put(eventType);
+    }
+  }
+}

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/AddToProjectList.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/AddToProjectList.java
index f7af2df..6f47da3 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/AddToProjectList.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/AddToProjectList.java

@@ -14,13 +14,16 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
+import java.time.Instant;
+
 public class AddToProjectList extends Command {
-  static final String TYPE = "add-to-project-list";
+  static final EventType TYPE = EventType.PROJECT_LIST_ADDITION;
 
   private final String projectName;
 
-  public AddToProjectList(String projectName) {
-    super(TYPE);
+  public AddToProjectList(String projectName, Instant eventCreatedOn) {
+    super(TYPE, eventCreatedOn);
     this.projectName = projectName;
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/Command.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/Command.java
index a258d91..3abad1e 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/Command.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/Command.java

@@ -14,10 +14,15 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
-public class Command {
-  public final String type;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
+import java.time.Instant;
 
-  protected Command(String type) {
+public class Command {
+  public final EventType type;
+  public final Instant eventCreatedOn;
+
+  protected Command(EventType type, Instant eventCreatedOn) {
     this.type = type;
+    this.eventCreatedOn = eventCreatedOn;
   }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/CommandDeserializer.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/CommandDeserializer.java
index b75f409..cdd217c 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/CommandDeserializer.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/CommandDeserializer.java

@@ -14,6 +14,7 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.google.gson.JsonDeserializationContext;
 import com.google.gson.JsonDeserializer;
 import com.google.gson.JsonElement;
@@ -29,6 +30,7 @@
   private static final List<Class<? extends Command>> CMD_CLASSES =
       List.of(
           IndexChange.Update.class,
+          IndexChange.BatchUpdate.class,
           IndexChange.Delete.class,
           IndexAccount.class,
           IndexGroup.class,
@@ -37,13 +39,13 @@
           PostEvent.class,
           AddToProjectList.class,
           RemoveFromProjectList.class);
-  private static final Map<String, Class<?>> COMMAND_TYPE_TO_CLASS_MAPPING = new HashMap<>();
+  private static final Map<EventType, Class<?>> COMMAND_TYPE_TO_CLASS_MAPPING = new HashMap<>();
 
   static {
     for (Class<?> clazz : CMD_CLASSES) {
       try {
         Field type = clazz.getDeclaredField("TYPE");
-        COMMAND_TYPE_TO_CLASS_MAPPING.put((String) type.get(null), clazz);
+        COMMAND_TYPE_TO_CLASS_MAPPING.put((EventType) type.get(null), clazz);
       } catch (Exception e) {
         throw new RuntimeException(e);
       }
@@ -63,7 +65,7 @@
       throw new JsonParseException("Type is not a string: " + typeJson);
     }
     String type = typeJson.getAsJsonPrimitive().getAsString();
-    Class<?> commandClass = COMMAND_TYPE_TO_CLASS_MAPPING.get(type);
+    Class<?> commandClass = COMMAND_TYPE_TO_CLASS_MAPPING.get(EventType.valueOf(type));
     if (commandClass == null) {
       throw new JsonParseException("Unknown command type: " + type);
     }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/DeleteAllProjectChangesFromIndex.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/DeleteAllProjectChangesFromIndex.java
index 79933fb..81ce445 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/DeleteAllProjectChangesFromIndex.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/DeleteAllProjectChangesFromIndex.java

@@ -14,15 +14,17 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.google.gerrit.entities.Project;
+import java.time.Instant;
 
 public class DeleteAllProjectChangesFromIndex extends Command {
-  static final String TYPE = "delete-all-project-changes-from-index";
+  static final EventType TYPE = EventType.INDEX_CHANGE_DELETION_ALL_OF_PROJECT;
 
   private final Project.NameKey projectName;
 
-  protected DeleteAllProjectChangesFromIndex(Project.NameKey projectName) {
-    super(TYPE);
+  protected DeleteAllProjectChangesFromIndex(Project.NameKey projectName, Instant createdOn) {
+    super(TYPE, createdOn);
     this.projectName = projectName;
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/EvictCache.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/EvictCache.java
index c4ae6d0..9ca05f1 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/EvictCache.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/EvictCache.java

@@ -14,14 +14,17 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
+import java.time.Instant;
+
 public class EvictCache extends Command {
-  static final String TYPE = "evict-cache";
+  static final EventType TYPE = EventType.CACHE_EVICTION;
 
   private final String cacheName;
   private final String keyJson;
 
-  protected EvictCache(String cacheName, String keyJson) {
-    super(TYPE);
+  protected EvictCache(String cacheName, String keyJson, Instant eventCreatedOn) {
+    super(TYPE, eventCreatedOn);
     this.cacheName = cacheName;
     this.keyJson = keyJson;
   }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/FailsafeExecutorProvider.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/FailsafeExecutorProvider.java
index 8f81832..be6bbf4 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/FailsafeExecutorProvider.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/FailsafeExecutorProvider.java

@@ -15,6 +15,7 @@
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
 import com.ericsson.gerrit.plugins.highavailability.Configuration;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder.Result;
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.server.git.WorkQueue;
 import com.google.inject.Inject;
@@ -23,7 +24,7 @@
 import dev.failsafe.FailsafeExecutor;
 import dev.failsafe.RetryPolicy;
 
-public class FailsafeExecutorProvider implements Provider<FailsafeExecutor<Boolean>> {
+public class FailsafeExecutorProvider implements Provider<FailsafeExecutor<Result>> {
   private static final FluentLogger log = FluentLogger.forEnclosingClass();
   private final Configuration cfg;
   private final WorkQueue workQueue;
@@ -35,9 +36,9 @@
   }
 
   @Override
-  public FailsafeExecutor<Boolean> get() {
-    RetryPolicy<Boolean> retryPolicy =
-        RetryPolicy.<Boolean>builder()
+  public FailsafeExecutor<Result> get() {
+    RetryPolicy<Result> retryPolicy =
+        RetryPolicy.<Result>builder()
             .withMaxAttempts(cfg.jgroups().maxTries())
             .withDelay(cfg.jgroups().retryInterval())
             .onRetry(e -> log.atFine().log("Retrying event %s", e))
@@ -45,7 +46,7 @@
                 e ->
                     log.atWarning().log(
                         "%d jgroups retries exceeded for event %s", cfg.jgroups().maxTries(), e))
-            .handleResult(false)
+            .handleResultIf(r -> !r.result())
             .build();
     return Failsafe.with(retryPolicy)
         .with(workQueue.createQueue(cfg.jgroups().threadPoolSize(), "JGroupsForwarder"));

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexAccount.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexAccount.java
index 7d9bbc4..55cadda 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexAccount.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexAccount.java

@@ -14,13 +14,16 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
+import java.time.Instant;
+
 public class IndexAccount extends Command {
-  static final String TYPE = "index-account";
+  static final EventType TYPE = EventType.INDEX_ACCOUNT_UPDATE;
 
   private final int id;
 
-  public IndexAccount(int id) {
-    super(TYPE);
+  public IndexAccount(int id, Instant eventCreatedOn) {
+    super(TYPE, eventCreatedOn);
     this.id = id;
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexChange.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexChange.java
index 501a722..075bfd7 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexChange.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexChange.java

@@ -14,15 +14,18 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.google.common.base.Strings;
+import java.time.Instant;
 
 public abstract class IndexChange extends Command {
   private final String projectName;
   private final int id;
   private final boolean batchMode;
 
-  protected IndexChange(String type, String projectName, int id, boolean batchMode) {
-    super(type);
+  protected IndexChange(
+      EventType type, String projectName, int id, boolean batchMode, Instant eventCreatedOn) {
+    super(type, eventCreatedOn);
     this.projectName = projectName;
     this.id = id;
     this.batchMode = batchMode;
@@ -37,26 +40,30 @@
   }
 
   public static class Update extends IndexChange {
-    static final String TYPE = "update-change";
+    static final EventType TYPE = EventType.INDEX_CHANGE_UPDATE;
 
-    public Update(String projectName, int id) {
-      this(projectName, id, false);
+    public Update(String projectName, int id, Instant eventCreatedOn) {
+      super(TYPE, projectName, id, false, eventCreatedOn);
     }
+  }
 
-    public Update(String projectName, int id, boolean batchMode) {
-      super(TYPE, projectName, id, batchMode);
+  public static class BatchUpdate extends IndexChange {
+    static final EventType TYPE = EventType.INDEX_CHANGE_UPDATE_BATCH;
+
+    public BatchUpdate(String projectName, int id, Instant eventCreatedOn) {
+      super(TYPE, projectName, id, true, eventCreatedOn);
     }
   }
 
   public static class Delete extends IndexChange {
-    static final String TYPE = "delete-change";
+    static final EventType TYPE = EventType.INDEX_CHANGE_DELETION;
 
-    public Delete(int id) {
-      this("", id);
+    public Delete(int id, Instant eventCreatedOn) {
+      this("", id, eventCreatedOn);
     }
 
-    public Delete(String projectName, int id) {
-      super(TYPE, projectName, id, false);
+    public Delete(String projectName, int id, Instant eventCreatedOn) {
+      super(TYPE, projectName, id, false, eventCreatedOn);
     }
   }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexGroup.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexGroup.java
index b5c9f78..9f49060 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexGroup.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexGroup.java

@@ -14,13 +14,16 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
+import java.time.Instant;
+
 public class IndexGroup extends Command {
-  static final String TYPE = "index-group";
+  static final EventType TYPE = EventType.INDEX_GROUP_UPDATE;
 
   private final String uuid;
 
-  protected IndexGroup(String uuid) {
-    super(TYPE);
+  protected IndexGroup(String uuid, Instant eventCreatedOn) {
+    super(TYPE, eventCreatedOn);
     this.uuid = uuid;
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexProject.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexProject.java
index 4d8214d..40e400d 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexProject.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/IndexProject.java

@@ -14,13 +14,16 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
+import java.time.Instant;
+
 public class IndexProject extends Command {
-  static final String TYPE = "index-project";
+  static final EventType TYPE = EventType.INDEX_PROJECT_UPDATE;
 
   private String projectName;
 
-  protected IndexProject(String projectName) {
-    super(TYPE);
+  protected IndexProject(String projectName, Instant eventCreatedOn) {
+    super(TYPE, eventCreatedOn);
     this.projectName = projectName;
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/InstantTypeAdapter.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/InstantTypeAdapter.java
new file mode 100644
index 0000000..df8780c
--- /dev/null
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/InstantTypeAdapter.java

@@ -0,0 +1,40 @@
+// Copyright (C) 2025 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
+
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonSerializationContext;
+import com.google.gson.JsonSerializer;
+import java.lang.reflect.Type;
+import java.time.Instant;
+
+public class InstantTypeAdapter implements JsonDeserializer<Instant>, JsonSerializer<Instant> {
+  @Override
+  public Instant deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)
+      throws JsonParseException {
+    if (json == null || !json.isJsonPrimitive() || !json.getAsJsonPrimitive().isNumber()) {
+      throw new JsonParseException("Invalid Instant value: " + json);
+    }
+    return Instant.ofEpochMilli(json.getAsLong());
+  }
+
+  @Override
+  public JsonElement serialize(Instant src, Type typeOfSrc, JsonSerializationContext context) {
+    return context.serialize(src.toEpochMilli(), Long.class);
+  }
+}

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarder.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarder.java
index 9f1f179..0bd8c5d 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarder.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarder.java

@@ -17,6 +17,7 @@
 import com.ericsson.gerrit.plugins.highavailability.Configuration;
 import com.ericsson.gerrit.plugins.highavailability.Configuration.JGroups;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwarderMetricsRegistry;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.IndexEvent;
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.entities.Project;
@@ -25,6 +26,8 @@
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import dev.failsafe.FailsafeExecutor;
+import java.time.Duration;
+import java.time.Instant;
 import java.util.List;
 import java.util.Map.Entry;
 import java.util.concurrent.CompletableFuture;
@@ -43,89 +46,106 @@
   private final MessageDispatcher dispatcher;
   private final JGroups jgroupsConfig;
   private final Gson gson;
-  private final FailsafeExecutor<Boolean> executor;
+  private final FailsafeExecutor<Result> executor;
+  private final ForwarderMetricsRegistry metricsRegistry;
 
   @Inject
   JGroupsForwarder(
       MessageDispatcher dispatcher,
       Configuration cfg,
       @JGroupsGson Gson gson,
-      @JGroupsForwarderExecutor FailsafeExecutor<Boolean> executor) {
+      @JGroupsForwarderExecutor FailsafeExecutor<Result> executor,
+      ForwarderMetricsRegistry metricsRegistry) {
     this.dispatcher = dispatcher;
     this.jgroupsConfig = cfg.jgroups();
     this.gson = gson;
     this.executor = executor;
+
+    this.metricsRegistry = metricsRegistry;
+    this.executor.onComplete(
+        ev -> {
+          this.metricsRegistry.get(ev.getResult().type()).recordRetries(ev.getAttemptCount());
+        });
   }
 
   @Override
-  public CompletableFuture<Boolean> indexAccount(int accountId, IndexEvent indexEvent) {
-    return execute(new IndexAccount(accountId));
+  public CompletableFuture<Result> indexAccount(int accountId, IndexEvent indexEvent) {
+    return execute(new IndexAccount(accountId, indexEvent.eventCreatedOn));
   }
 
   @Override
-  public CompletableFuture<Boolean> indexChange(
+  public CompletableFuture<Result> indexChange(
       String projectName, int changeId, IndexEvent indexEvent) {
-    return execute(new IndexChange.Update(projectName, changeId));
+    return execute(new IndexChange.Update(projectName, changeId, indexEvent.eventCreatedOn));
   }
 
   @Override
-  public CompletableFuture<Boolean> batchIndexChange(
+  public CompletableFuture<Result> batchIndexChange(
       String projectName, int changeId, IndexEvent indexEvent) {
-    return execute(new IndexChange.Update(projectName, changeId, true));
+    return execute(new IndexChange.BatchUpdate(projectName, changeId, indexEvent.eventCreatedOn));
   }
 
   @Override
-  public CompletableFuture<Boolean> deleteChangeFromIndex(int changeId, IndexEvent indexEvent) {
-    return execute(new IndexChange.Delete(changeId));
+  public CompletableFuture<Result> deleteChangeFromIndex(int changeId, IndexEvent indexEvent) {
+    return execute(new IndexChange.Delete(changeId, indexEvent.eventCreatedOn));
   }
 
   @Override
-  public CompletableFuture<Boolean> indexGroup(String uuid, IndexEvent indexEvent) {
-    return execute(new IndexGroup(uuid));
+  public CompletableFuture<Result> indexGroup(String uuid, IndexEvent indexEvent) {
+    return execute(new IndexGroup(uuid, indexEvent.eventCreatedOn));
   }
 
   @Override
-  public CompletableFuture<Boolean> indexProject(String projectName, IndexEvent indexEvent) {
-    return execute(new IndexProject(projectName));
+  public CompletableFuture<Result> indexProject(String projectName, IndexEvent indexEvent) {
+    return execute(new IndexProject(projectName, indexEvent.eventCreatedOn));
   }
 
   @Override
-  public CompletableFuture<Boolean> send(Event event) {
-    return execute(new PostEvent(event));
+  public CompletableFuture<Result> send(Event event) {
+    return execute(new PostEvent(event, Instant.ofEpochSecond(event.eventCreatedOn)));
   }
 
   @Override
-  public CompletableFuture<Boolean> evict(String cacheName, Object key) {
-    return execute(new EvictCache(cacheName, gson.toJson(key)));
+  public CompletableFuture<Result> evict(String cacheName, Object key) {
+    return execute(new EvictCache(cacheName, gson.toJson(key), Instant.now()));
   }
 
   @Override
-  public CompletableFuture<Boolean> addToProjectList(String projectName) {
-    return execute(new AddToProjectList(projectName));
+  public CompletableFuture<Result> addToProjectList(String projectName) {
+    return execute(new AddToProjectList(projectName, Instant.now()));
   }
 
   @Override
-  public CompletableFuture<Boolean> removeFromProjectList(String projectName) {
-    return execute(new RemoveFromProjectList(projectName));
+  public CompletableFuture<Result> removeFromProjectList(String projectName) {
+    return execute(new RemoveFromProjectList(projectName, Instant.now()));
   }
 
   @Override
-  public CompletableFuture<Boolean> deleteAllChangesForProject(Project.NameKey projectName) {
-    return execute(new DeleteAllProjectChangesFromIndex(projectName));
+  public CompletableFuture<Result> deleteAllChangesForProject(Project.NameKey projectName) {
+    return execute(new DeleteAllProjectChangesFromIndex(projectName, Instant.now()));
   }
 
-  private CompletableFuture<Boolean> execute(Command cmd) {
-    return executor.getAsync(() -> executeOnce(cmd));
+  private CompletableFuture<Result> execute(Command cmd) {
+    return executor
+        .getAsync(() -> executeOnce(cmd))
+        .thenApplyAsync(
+            result -> {
+              metricsRegistry.get(cmd.type).recordResult(result.result());
+              metricsRegistry
+                  .get(cmd.type)
+                  .recordLatency(Duration.between(cmd.eventCreatedOn, Instant.now()).toMillis());
+              return result;
+            });
   }
 
-  private boolean executeOnce(Command cmd) {
+  private Result executeOnce(Command cmd) {
     String json = gson.toJson(cmd);
     try {
       logJGroupsInfo();
 
       if (dispatcher.getChannel().getView().size() < 2) {
         log.atFine().log("Less than two members in cluster, not sending %s", json);
-        return false;
+        return new Result(cmd.type, false);
       }
 
       log.atFine().log("Sending %s", json);
@@ -135,7 +155,7 @@
 
       log.atFine().log("Received response list length = %s", list.size());
       if (list.isEmpty()) {
-        return false;
+        return new Result(cmd.type, false);
       }
 
       for (Entry<Address, Rsp<Object>> e : list.entrySet()) {
@@ -144,14 +164,14 @@
           log.atWarning().log(
               "Received a non TRUE response from receiver %s: %s",
               e.getKey(), e.getValue().getValue());
-          return false;
+          return new Result(cmd.type, false);
         }
       }
       log.atFine().log("Successfully sent message %s", json);
-      return true;
+      return new Result(cmd.type, true);
     } catch (Exception e) {
       log.atWarning().withCause(e).log("Forwarding %s failed", json);
-      return false;
+      return new Result(cmd.type, false);
     }
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarderModule.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarderModule.java
index 58e7aeb..360ba40 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarderModule.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarderModule.java

@@ -15,6 +15,7 @@
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder.Result;
 import com.ericsson.gerrit.plugins.highavailability.peers.jgroups.JChannelProviderModule;
 import com.google.gerrit.lifecycle.LifecycleModule;
 import com.google.gerrit.server.events.EventGson;
@@ -24,6 +25,7 @@
 import com.google.inject.Singleton;
 import com.google.inject.TypeLiteral;
 import dev.failsafe.FailsafeExecutor;
+import java.time.Instant;
 import org.jgroups.blocks.MessageDispatcher;
 import org.jgroups.blocks.RequestHandler;
 
@@ -37,7 +39,7 @@
     install(new JChannelProviderModule());
     listener().to(OnStartStop.class);
 
-    bind(new TypeLiteral<FailsafeExecutor<Boolean>>() {})
+    bind(new TypeLiteral<FailsafeExecutor<Result>>() {})
         .annotatedWith(JGroupsForwarderExecutor.class)
         .toProvider(FailsafeExecutorProvider.class)
         .in(Scopes.SINGLETON);
@@ -50,6 +52,7 @@
     return eventGson
         .newBuilder()
         .registerTypeAdapter(Command.class, new CommandDeserializer())
+        .registerTypeAdapter(Instant.class, new InstantTypeAdapter())
         .create();
   }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/MessageProcessor.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/MessageProcessor.java
index 73df3eb..489e070 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/MessageProcessor.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/MessageProcessor.java

@@ -23,6 +23,8 @@
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexChangeHandler;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexingHandler.Operation;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedProjectListUpdateHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.server.events.Event;
@@ -30,6 +32,7 @@
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
+import java.time.Instant;
 import java.util.Optional;
 import org.jgroups.Message;
 import org.jgroups.blocks.RequestHandler;
@@ -45,6 +48,7 @@
   private final ForwardedCacheEvictionHandler cacheEvictionHandler;
   private final ForwardedEventHandler eventHandler;
   private final ForwardedProjectListUpdateHandler projectListUpdateHandler;
+  private final ProcessorMetricsRegistry metricRegistry;
 
   @Inject
   MessageProcessor(
@@ -54,7 +58,8 @@
       ForwardedIndexAccountHandler indexAccountHandler,
       ForwardedCacheEvictionHandler cacheEvictionHandler,
       ForwardedEventHandler eventHandler,
-      ForwardedProjectListUpdateHandler projectListUpdateHandler) {
+      ForwardedProjectListUpdateHandler projectListUpdateHandler,
+      ProcessorMetricsRegistry metricRegistry) {
     this.gson = gson;
     this.indexChangeHandler = indexChangeHandler;
     this.indexBatchChangeHandler = indexBatchChangeHandler;
@@ -62,11 +67,15 @@
     this.cacheEvictionHandler = cacheEvictionHandler;
     this.eventHandler = eventHandler;
     this.projectListUpdateHandler = projectListUpdateHandler;
+    this.metricRegistry = metricRegistry;
   }
 
   @Override
   public Object handle(Message msg) {
     Command cmd = getCommand(msg);
+    ProcessorMetrics metrics = metricRegistry.get(cmd.type);
+    Instant startTime = Instant.now();
+    boolean success = false;
 
     Context.setForwardedEvent(true);
     try {
@@ -83,7 +92,7 @@
         } catch (Exception e) {
           log.atSevere().withCause(e).log(
               "Change index %s on change %s failed", op.name().toLowerCase(), indexChange.getId());
-          return false;
+          throw e;
         }
 
       } else if (cmd instanceof IndexAccount) {
@@ -95,7 +104,7 @@
         } catch (IOException e) {
           log.atSevere().withCause(e).log(
               "Account index update on account %s failed", indexAccount.getId());
-          return false;
+          throw e;
         }
 
       } else if (cmd instanceof EvictCache) {
@@ -117,17 +126,18 @@
         String projectName = ((RemoveFromProjectList) cmd).getProjectName();
         projectListUpdateHandler.update(projectName, true);
       }
-
-      return true;
+      success = true;
     } catch (Exception e) {
-      return false;
+      success = false;
     } finally {
       Context.unsetForwardedEvent();
     }
+    metrics.record(cmd.eventCreatedOn, startTime, success);
+    return success;
   }
 
   private Operation getOperation(IndexChange cmd) {
-    if (cmd instanceof IndexChange.Update) {
+    if (cmd instanceof IndexChange.Update || cmd instanceof IndexChange.BatchUpdate) {
       return Operation.INDEX;
     } else if (cmd instanceof IndexChange.Delete) {
       return Operation.DELETE;

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/PostEvent.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/PostEvent.java
index 49627a7..3f50b0a 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/PostEvent.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/PostEvent.java

@@ -14,15 +14,17 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.google.gerrit.server.events.Event;
+import java.time.Instant;
 
 public class PostEvent extends Command {
-  static final String TYPE = "post-event";
+  static final EventType TYPE = EventType.EVENT_SENT;
 
   private final Event event;
 
-  protected PostEvent(Event event) {
-    super(TYPE);
+  protected PostEvent(Event event, Instant eventCreatedOn) {
+    super(TYPE, eventCreatedOn);
     this.event = event;
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/RemoveFromProjectList.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/RemoveFromProjectList.java
index 8eb0a3d..1a43ac8 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/RemoveFromProjectList.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/RemoveFromProjectList.java

@@ -14,13 +14,16 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
+import java.time.Instant;
+
 public class RemoveFromProjectList extends Command {
-  static final String TYPE = "remove-from-project-list";
+  static final EventType TYPE = EventType.PROJECT_LIST_DELETION;
 
   private final String projectName;
 
-  public RemoveFromProjectList(String projectName) {
-    super(TYPE);
+  public RemoveFromProjectList(String projectName, Instant eventCreatedOn) {
+    super(TYPE, eventCreatedOn);
     this.projectName = projectName;
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/AbstractIndexRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/AbstractIndexRestApiServlet.java
index a567f61..52b3ece 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/AbstractIndexRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/AbstractIndexRestApiServlet.java

@@ -18,10 +18,14 @@
 import static javax.servlet.http.HttpServletResponse.SC_METHOD_NOT_ALLOWED;
 import static javax.servlet.http.HttpServletResponse.SC_NO_CONTENT;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexingHandler;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexingHandler.Operation;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.IndexEvent;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.common.base.Charsets;
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.extensions.restapi.NotImplementedException;
 import com.google.gerrit.server.events.EventGson;
 import com.google.gson.Gson;
 import java.io.IOException;
@@ -56,45 +60,52 @@
   AbstractIndexRestApiServlet(
       ForwardedIndexingHandler<T> forwardedIndexingHandler,
       IndexName indexName,
-      boolean allowDelete,
-      @EventGson Gson gson) {
+      @EventGson Gson gson,
+      ProcessorMetricsRegistry metricsRegistry,
+      EventType postEventType,
+      @Nullable EventType deleteEventType) {
+    super(metricsRegistry, postEventType, deleteEventType);
     this.forwardedIndexingHandler = forwardedIndexingHandler;
     this.indexName = indexName;
-    this.allowDelete = allowDelete;
     this.gson = gson;
-  }
-
-  AbstractIndexRestApiServlet(
-      ForwardedIndexingHandler<T> forwardedIndexingHandler, IndexName indexName) {
-    this(forwardedIndexingHandler, indexName, false, new Gson());
+    this.allowDelete = deleteEventType != null;
   }
 
   @Override
-  protected void doPost(HttpServletRequest req, HttpServletResponse rsp) {
-    process(req, rsp, Operation.INDEX);
+  protected boolean processPostRequest(HttpServletRequest req, HttpServletResponse rsp) {
+    return process(req, rsp, Operation.INDEX);
   }
 
   @Override
-  protected void doDelete(HttpServletRequest req, HttpServletResponse rsp) {
+  protected boolean processDeleteRequest(HttpServletRequest req, HttpServletResponse rsp) {
     if (!allowDelete) {
       sendError(
           rsp, SC_METHOD_NOT_ALLOWED, String.format("cannot delete %s from index", indexName));
-    } else {
-      process(req, rsp, Operation.DELETE);
+      throw new NotImplementedException("Deletions not allowed for " + indexName);
     }
+    return process(req, rsp, Operation.DELETE);
   }
 
-  private void process(HttpServletRequest req, HttpServletResponse rsp, Operation operation) {
-    setHeaders(rsp);
+  /**
+   * Process the request by parsing the ID from the URL and invoking the indexing handler.
+   *
+   * @param req the HTTP request
+   * @param rsp the HTTP response
+   * @param operation the indexing operation to perform (INDEX or DELETE)
+   * @return true if the operation was successful, false otherwise
+   */
+  private boolean process(HttpServletRequest req, HttpServletResponse rsp, Operation operation) {
     String path = req.getRequestURI();
     T id = parse(path.substring(path.lastIndexOf('/') + 1));
 
     try {
       forwardedIndexingHandler.index(id, operation, parseBody(req));
       rsp.setStatus(SC_NO_CONTENT);
+      return true;
     } catch (IOException e) {
       sendError(rsp, SC_CONFLICT, e.getMessage());
       log.atSevere().withCause(e).log("Unable to update %s index", indexName);
+      return false;
     }
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/AbstractRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/AbstractRestApiServlet.java
index a76d8ea..6aa0461 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/AbstractRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/AbstractRestApiServlet.java

@@ -16,20 +16,88 @@
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
+import com.google.common.base.Strings;
 import com.google.common.flogger.FluentLogger;
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.extensions.restapi.NotImplementedException;
 import java.io.IOException;
+import java.time.Instant;
 import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 public abstract class AbstractRestApiServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;
   protected static final FluentLogger log = FluentLogger.forEnclosingClass();
 
+  private final ProcessorMetrics postMetrics;
+  private final ProcessorMetrics deleteMetrics;
+
+  public AbstractRestApiServlet(
+      ProcessorMetricsRegistry metricsRegistry,
+      EventType postEventType,
+      @Nullable EventType deleteEventType) {
+    super();
+    this.postMetrics = metricsRegistry.get(postEventType);
+    if (deleteEventType != null) {
+      this.deleteMetrics = metricsRegistry.get(deleteEventType);
+    } else {
+      this.deleteMetrics = null;
+    }
+  }
+
   protected static void setHeaders(HttpServletResponse rsp) {
     rsp.setContentType("text/plain");
     rsp.setCharacterEncoding(UTF_8.name());
   }
 
+  @Override
+  public final void doPost(HttpServletRequest req, HttpServletResponse rsp) {
+    setHeaders(rsp);
+    Instant start = Instant.now();
+
+    boolean success = processPostRequest(req, rsp);
+
+    postMetrics.record(getEventCreatedOnFromHeader(req), start, success);
+  }
+
+  @Override
+  public final void doDelete(HttpServletRequest req, HttpServletResponse rsp) {
+    setHeaders(rsp);
+    Instant start = Instant.now();
+
+    try {
+      boolean success = processDeleteRequest(req, rsp);
+      deleteMetrics.record(getEventCreatedOnFromHeader(req), start, success);
+    } catch (NotImplementedException e) {
+      return;
+    }
+  }
+
+  private Instant getEventCreatedOnFromHeader(HttpServletRequest req) {
+    String header = req.getHeader(HttpSession.HEADER_EVENT_CREATED_ON);
+    if (!Strings.isNullOrEmpty(header)) {
+      try {
+        return Instant.ofEpochMilli(Long.valueOf(header));
+      } catch (NumberFormatException e) {
+        log.atWarning().withCause(e).log(
+            "Invalid value for header %s: %s", HttpSession.HEADER_EVENT_CREATED_ON, header);
+      }
+    }
+    return null;
+  }
+
+  protected boolean processPostRequest(HttpServletRequest req, HttpServletResponse rsp) {
+    throw new NotImplementedException("POST requests not implemented");
+  }
+
+  protected boolean processDeleteRequest(HttpServletRequest req, HttpServletResponse rsp) {
+    throw new NotImplementedException("DELETE requests not implemented");
+  }
+
   protected void sendError(HttpServletResponse rsp, int statusCode, String message) {
     try {
       rsp.sendError(statusCode, message);
@@ -37,4 +105,19 @@
       log.atSevere().withCause(e).log("Failed to send error messsage");
     }
   }
+
+  protected static void updateMetrics(
+      ProcessorMetrics metrics, HttpServletRequest req, Instant startTime, boolean success) {
+    String eventCreatedOn = req.getHeader(HttpSession.HEADER_EVENT_CREATED_ON);
+    Instant now = Instant.now();
+    long totalDuration;
+    if (Strings.isNullOrEmpty(eventCreatedOn)) {
+      totalDuration = 0L;
+    } else {
+      totalDuration = now.toEpochMilli() - Long.valueOf(eventCreatedOn);
+    }
+    metrics.recordResult(success);
+    metrics.recordProcessingTime(now.toEpochMilli() - startTime.toEpochMilli());
+    metrics.recordTotalTime(totalDuration);
+  }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheKeyJsonParser.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheKeyJsonParser.java
index b8f5e9c..16e25a9 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheKeyJsonParser.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheKeyJsonParser.java

@@ -15,6 +15,7 @@
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
 import com.ericsson.gerrit.plugins.highavailability.cache.Constants;
+import com.google.common.base.CharMatcher;
 import com.google.common.base.Strings;
 import com.google.common.base.Supplier;
 import com.google.common.base.Suppliers;
@@ -54,7 +55,7 @@
       case Constants.PROJECT_LIST:
         return gson.fromJson(json, Object.class);
       case Constants.PROJECTS:
-        return Project.nameKey(json.getAsString());
+        return Project.nameKey(CharMatcher.is('\"').trimFrom(json.getAsString()));
       default:
         try {
           return gson.fromJson(json, String.class);

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheRestApiServlet.java
index 86d64d2..926776b 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheRestApiServlet.java

@@ -19,7 +19,9 @@
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.CacheEntry;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.CacheNotFoundException;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedCacheEvictionHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.common.base.Splitter;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
@@ -39,13 +41,15 @@
   @Inject
   CacheRestApiServlet(
       ForwardedCacheEvictionHandler forwardedCacheEvictionHandler,
-      CacheKeyJsonParser cacheKeyParser) {
+      CacheKeyJsonParser cacheKeyParser,
+      ProcessorMetricsRegistry metricRegistry) {
+    super(metricRegistry, EventType.CACHE_EVICTION, null);
     this.forwardedCacheEvictionHandler = forwardedCacheEvictionHandler;
     this.cacheKeyParser = cacheKeyParser;
   }
 
   @Override
-  protected void doPost(HttpServletRequest req, HttpServletResponse rsp) {
+  protected boolean processPostRequest(HttpServletRequest req, HttpServletResponse rsp) {
     setHeaders(rsp);
     try {
       List<String> params = Splitter.on('/').splitToList(req.getPathInfo());
@@ -54,6 +58,7 @@
       forwardedCacheEvictionHandler.evict(
           CacheEntry.from(cacheName, cacheKeyParser.fromJson(cacheName, json)));
       rsp.setStatus(SC_NO_CONTENT);
+      return true;
     } catch (CacheNotFoundException e) {
       log.atSevere().log("Failed to process eviction request: %s", e.getMessage());
       sendError(rsp, SC_BAD_REQUEST, e.getMessage());
@@ -61,5 +66,6 @@
       log.atSevere().withCause(e).log("Failed to process eviction request");
       sendError(rsp, SC_BAD_REQUEST, e.getMessage());
     }
+    return false;
   }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/EventRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/EventRestApiServlet.java
index e2e3302..973844d 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/EventRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/EventRestApiServlet.java

@@ -19,7 +19,9 @@
 import static javax.servlet.http.HttpServletResponse.SC_NO_CONTENT;
 import static javax.servlet.http.HttpServletResponse.SC_UNSUPPORTED_MEDIA_TYPE;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedEventHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.common.io.CharStreams;
 import com.google.common.net.MediaType;
 import com.google.gerrit.server.events.Event;
@@ -39,24 +41,29 @@
   private final Gson gson;
 
   @Inject
-  EventRestApiServlet(ForwardedEventHandler forwardedEventHandler, @EventGson Gson gson) {
+  EventRestApiServlet(
+      ForwardedEventHandler forwardedEventHandler,
+      @EventGson Gson gson,
+      ProcessorMetricsRegistry metricRegistry) {
+    super(metricRegistry, EventType.EVENT_SENT, null);
     this.forwardedEventHandler = forwardedEventHandler;
     this.gson = gson;
   }
 
   @Override
-  protected void doPost(HttpServletRequest req, HttpServletResponse rsp) {
-    setHeaders(rsp);
+  protected boolean processPostRequest(HttpServletRequest req, HttpServletResponse rsp) {
     try {
       if (!MediaType.parse(req.getContentType()).is(JSON_UTF_8)) {
         sendError(rsp, SC_UNSUPPORTED_MEDIA_TYPE, "Expecting " + JSON_UTF_8 + " content type");
-        return;
+        return false;
       }
       Event event = getEventFromRequest(req);
       rsp.setStatus(SC_NO_CONTENT);
       forwardedEventHandler.dispatch(event);
+      return true;
     } catch (IOException e) {
       sendError(rsp, SC_BAD_REQUEST, e.getMessage());
+      return false;
     }
   }
 

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/FailsafeExecutorProvider.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/FailsafeExecutorProvider.java
index 8134220..6168880 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/FailsafeExecutorProvider.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/FailsafeExecutorProvider.java

@@ -15,18 +15,18 @@
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
 import com.ericsson.gerrit.plugins.highavailability.Configuration;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder.Result;
 import com.google.common.flogger.FluentLogger;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import dev.failsafe.Failsafe;
 import dev.failsafe.FailsafeExecutor;
-import dev.failsafe.Fallback;
 import dev.failsafe.RetryPolicy;
 import java.util.concurrent.Executors;
 
 @Singleton
-public class FailsafeExecutorProvider implements Provider<FailsafeExecutor<Boolean>> {
+public class FailsafeExecutorProvider implements Provider<FailsafeExecutor<Result>> {
   private static final FluentLogger log = FluentLogger.forEnclosingClass();
   private final Configuration cfg;
 
@@ -36,10 +36,9 @@
   }
 
   @Override
-  public FailsafeExecutor<Boolean> get() {
-    Fallback<Boolean> fallbackToFalse = Fallback.<Boolean>of(() -> false);
-    RetryPolicy<Boolean> retryPolicy =
-        RetryPolicy.<Boolean>builder()
+  public FailsafeExecutor<Result> get() {
+    RetryPolicy<Result> retryPolicy =
+        RetryPolicy.<Result>builder()
             .withMaxAttempts(cfg.http().maxTries())
             .withDelay(cfg.http().retryInterval())
             .onRetry(e -> log.atFine().log("Retrying event %s", e))
@@ -47,15 +46,13 @@
                 e ->
                     log.atWarning().log(
                         "%d http retries exceeded for event %s", cfg.http().maxTries(), e))
-            .handleResult(false)
-            .abortIf(
-                (r, e) ->
-                    e instanceof ForwardingException && !((ForwardingException) e).isRecoverable())
+            .handleResultIf(r -> !r.result())
+            .abortIf((r, e) -> !r.result() && !r.isRecoverable())
             .build();
     // TODO: the executor shall be created by workQueue.createQueue(...)
     //   However, this currently doesn't work because WorkQueue.Executor doesn't support wrapping of
     //   Callable i.e. it throws an exception on decorateTask(Callable)
-    return Failsafe.with(fallbackToFalse, retryPolicy)
+    return Failsafe.with(retryPolicy)
         .with(Executors.newScheduledThreadPool(cfg.http().threadPoolSize()));
   }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/HttpSession.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/HttpSession.java
index 6d801f6..53b8dc7 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/HttpSession.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/HttpSession.java

@@ -14,6 +14,7 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups.InstantTypeAdapter;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.rest.HttpResponseHandler.HttpResult;
 import com.google.common.net.MediaType;
 import com.google.gerrit.server.events.EventGson;
@@ -22,6 +23,7 @@
 import java.io.IOException;
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
+import java.time.Instant;
 import org.apache.http.client.methods.HttpDelete;
 import org.apache.http.client.methods.HttpEntityEnclosingRequestBase;
 import org.apache.http.client.methods.HttpPost;
@@ -29,40 +31,46 @@
 import org.apache.http.impl.client.CloseableHttpClient;
 
 class HttpSession {
+  public static final String HEADER_EVENT_CREATED_ON = "Event-Created-On";
+
   private final CloseableHttpClient httpClient;
   private final Gson gson;
 
   @Inject
   HttpSession(CloseableHttpClient httpClient, @EventGson Gson gson) {
     this.httpClient = httpClient;
-    this.gson = gson;
+
+    this.gson =
+        gson.newBuilder().registerTypeAdapter(Instant.class, new InstantTypeAdapter()).create();
   }
 
-  HttpResult post(String uri) throws IOException {
-    return post(uri, null);
+  HttpResult post(String uri, Instant createdOn) throws IOException {
+    return post(uri, null, createdOn);
   }
 
-  HttpResult post(String uri, Object content) throws IOException {
+  HttpResult post(String uri, Object content, Instant createdOn) throws IOException {
     HttpPost post = new HttpPost(uri);
-    setContent(post, content);
+    setContent(post, content, createdOn);
     return httpClient.execute(post, new HttpResponseHandler());
   }
 
-  HttpResult delete(String uri) throws IOException {
-    return delete(uri, null);
+  HttpResult delete(String uri, Instant createdOn) throws IOException {
+    return delete(uri, null, createdOn);
   }
 
-  HttpResult delete(String uri, Object content) throws IOException {
+  HttpResult delete(String uri, Object content, Instant createdOn) throws IOException {
     HttpDeleteWithBody delete = new HttpDeleteWithBody(uri);
-    setContent(delete, content);
+    setContent(delete, content, createdOn);
     return httpClient.execute(delete, new HttpResponseHandler());
   }
 
-  private void setContent(HttpEntityEnclosingRequestBase request, Object content) {
+  private void setContent(
+      HttpEntityEnclosingRequestBase request, Object content, Instant createdOn) {
     if (content != null) {
       request.addHeader("Content-Type", MediaType.JSON_UTF_8.toString());
       request.setEntity(new StringEntity(jsonEncode(content), StandardCharsets.UTF_8));
     }
+    request.addHeader(HEADER_EVENT_CREATED_ON, String.valueOf(createdOn.toEpochMilli()));
   }
 
   private String jsonEncode(Object content) {

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexAccountRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexAccountRestApiServlet.java
index fa38cc3..047da64 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexAccountRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexAccountRestApiServlet.java

@@ -14,8 +14,12 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexAccountHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.entities.Account;
+import com.google.gerrit.server.events.EventGson;
+import com.google.gson.Gson;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
@@ -24,8 +28,11 @@
   private static final long serialVersionUID = -1L;
 
   @Inject
-  IndexAccountRestApiServlet(ForwardedIndexAccountHandler handler) {
-    super(handler, IndexName.ACCOUNT);
+  IndexAccountRestApiServlet(
+      ForwardedIndexAccountHandler handler,
+      @EventGson Gson gson,
+      ProcessorMetricsRegistry metricRegistry) {
+    super(handler, IndexName.ACCOUNT, gson, metricRegistry, EventType.INDEX_ACCOUNT_UPDATE, null);
   }
 
   @Override

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexBatchChangeRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexBatchChangeRestApiServlet.java
index bebfae9..5816cb5 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexBatchChangeRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexBatchChangeRestApiServlet.java

@@ -14,7 +14,9 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexBatchChangeHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.extensions.restapi.Url;
 import com.google.gerrit.server.events.EventGson;
 import com.google.gson.Gson;
@@ -26,8 +28,12 @@
   private static final long serialVersionUID = -1L;
 
   @Inject
-  IndexBatchChangeRestApiServlet(ForwardedIndexBatchChangeHandler handler, @EventGson Gson gson) {
-    super(handler, IndexName.CHANGE, true, gson);
+  IndexBatchChangeRestApiServlet(
+      ForwardedIndexBatchChangeHandler handler,
+      @EventGson Gson gson,
+      ProcessorMetricsRegistry metricRegistry) {
+    super(
+        handler, IndexName.CHANGE, gson, metricRegistry, EventType.INDEX_CHANGE_UPDATE_BATCH, null);
   }
 
   @Override

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexChangeRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexChangeRestApiServlet.java
index 71e10fb..4d8d9a3 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexChangeRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexChangeRestApiServlet.java

@@ -14,7 +14,9 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexChangeHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.extensions.restapi.Url;
 import com.google.gerrit.server.events.EventGson;
 import com.google.gson.Gson;
@@ -26,8 +28,17 @@
   private static final long serialVersionUID = -1L;
 
   @Inject
-  IndexChangeRestApiServlet(ForwardedIndexChangeHandler handler, @EventGson Gson gson) {
-    super(handler, IndexName.CHANGE, true, gson);
+  IndexChangeRestApiServlet(
+      ForwardedIndexChangeHandler handler,
+      @EventGson Gson gson,
+      ProcessorMetricsRegistry metricRegistry) {
+    super(
+        handler,
+        IndexName.CHANGE,
+        gson,
+        metricRegistry,
+        EventType.INDEX_CHANGE_UPDATE,
+        EventType.INDEX_CHANGE_DELETION);
   }
 
   @Override

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexGroupRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexGroupRestApiServlet.java
index 35c526f..ed9b57e 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexGroupRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexGroupRestApiServlet.java

@@ -14,8 +14,12 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexGroupHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.entities.AccountGroup;
+import com.google.gerrit.server.events.EventGson;
+import com.google.gson.Gson;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
@@ -24,8 +28,11 @@
   private static final long serialVersionUID = -1L;
 
   @Inject
-  IndexGroupRestApiServlet(ForwardedIndexGroupHandler handler) {
-    super(handler, IndexName.GROUP);
+  IndexGroupRestApiServlet(
+      ForwardedIndexGroupHandler handler,
+      @EventGson Gson gson,
+      ProcessorMetricsRegistry metricRegistry) {
+    super(handler, IndexName.GROUP, gson, metricRegistry, EventType.INDEX_GROUP_UPDATE, null);
   }
 
   @Override

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexProjectRestApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexProjectRestApiServlet.java
index 31df2bb..fbf7ffd 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexProjectRestApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexProjectRestApiServlet.java

@@ -14,9 +14,13 @@
 
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexProjectHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.restapi.Url;
+import com.google.gerrit.server.events.EventGson;
+import com.google.gson.Gson;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
@@ -25,8 +29,11 @@
   private static final long serialVersionUID = -1L;
 
   @Inject
-  IndexProjectRestApiServlet(ForwardedIndexProjectHandler handler) {
-    super(handler, IndexName.PROJECT);
+  IndexProjectRestApiServlet(
+      ForwardedIndexProjectHandler handler,
+      @EventGson Gson gson,
+      ProcessorMetricsRegistry metricRegistry) {
+    super(handler, IndexName.PROJECT, gson, metricRegistry, EventType.INDEX_PROJECT_UPDATE, null);
   }
 
   @Override

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ProjectListApiServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ProjectListApiServlet.java
index 7a31ea0..fb88edb 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ProjectListApiServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ProjectListApiServlet.java

@@ -17,7 +17,9 @@
 import static javax.servlet.http.HttpServletResponse.SC_BAD_REQUEST;
 import static javax.servlet.http.HttpServletResponse.SC_NO_CONTENT;
 
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedProjectListUpdateHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.extensions.restapi.Url;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
@@ -32,30 +34,34 @@
   private final ForwardedProjectListUpdateHandler forwardedProjectListUpdateHandler;
 
   @Inject
-  ProjectListApiServlet(ForwardedProjectListUpdateHandler forwardedProjectListUpdateHandler) {
+  ProjectListApiServlet(
+      ForwardedProjectListUpdateHandler forwardedProjectListUpdateHandler,
+      ProcessorMetricsRegistry metricRegistry) {
+    super(metricRegistry, EventType.PROJECT_LIST_ADDITION, EventType.PROJECT_LIST_DELETION);
     this.forwardedProjectListUpdateHandler = forwardedProjectListUpdateHandler;
   }
 
   @Override
-  protected void doPost(HttpServletRequest req, HttpServletResponse rsp) {
-    process(req, rsp, false);
+  protected boolean processPostRequest(HttpServletRequest req, HttpServletResponse rsp) {
+    return process(req, rsp, false);
   }
 
   @Override
-  protected void doDelete(HttpServletRequest req, HttpServletResponse rsp) {
-    process(req, rsp, true);
+  protected boolean processDeleteRequest(HttpServletRequest req, HttpServletResponse rsp) {
+    return process(req, rsp, true);
   }
 
-  private void process(HttpServletRequest req, HttpServletResponse rsp, boolean delete) {
-    setHeaders(rsp);
+  private boolean process(HttpServletRequest req, HttpServletResponse rsp, boolean delete) {
     String requestURI = req.getRequestURI();
     String projectName = requestURI.substring(requestURI.lastIndexOf('/') + 1);
     try {
       forwardedProjectListUpdateHandler.update(Url.decode(projectName), delete);
       rsp.setStatus(SC_NO_CONTENT);
+      return true;
     } catch (IOException e) {
       log.atSevere().withCause(e).log("Unable to update project list");
       sendError(rsp, SC_BAD_REQUEST, e.getMessage());
+      return false;
     }
   }
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/QueryChangesUpdatedSinceServlet.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/QueryChangesUpdatedSinceServlet.java
index 4ebf175..244831e 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/QueryChangesUpdatedSinceServlet.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/QueryChangesUpdatedSinceServlet.java

@@ -32,11 +32,12 @@
 import java.io.PrintWriter;
 import java.util.ArrayList;
 import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 @Singleton
-public class QueryChangesUpdatedSinceServlet extends AbstractRestApiServlet {
+public class QueryChangesUpdatedSinceServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;
 
   Gson gson = new Gson();

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarder.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarder.java
index d53cd82..b7ad165 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarder.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarder.java

@@ -16,7 +16,9 @@
 
 import com.ericsson.gerrit.plugins.highavailability.Configuration;
 import com.ericsson.gerrit.plugins.highavailability.cache.Constants;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwarderMetricsRegistry;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.IndexEvent;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.rest.HttpResponseHandler.HttpResult;
 import com.ericsson.gerrit.plugins.highavailability.peers.PeerInfo;
@@ -33,6 +35,8 @@
 import com.google.inject.Provider;
 import dev.failsafe.FailsafeExecutor;
 import java.io.IOException;
+import java.time.Duration;
+import java.time.Instant;
 import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 import javax.net.ssl.SSLException;
@@ -54,7 +58,8 @@
   private final Configuration cfg;
   private final Provider<Set<PeerInfo>> peerInfoProvider;
   private final Gson gson;
-  private FailsafeExecutor<Boolean> executor;
+  private FailsafeExecutor<Result> executor;
+  private final ForwarderMetricsRegistry metricsRegistry;
 
   @Inject
   RestForwarder(
@@ -63,51 +68,80 @@
       Configuration cfg,
       Provider<Set<PeerInfo>> peerInfoProvider,
       @EventGson Gson gson,
-      @RestForwarderExecutor FailsafeExecutor<Boolean> executor) {
+      @RestForwarderExecutor FailsafeExecutor<Result> executor,
+      ForwarderMetricsRegistry metricsRegistry) {
     this.httpSession = httpClient;
     this.pluginRelativePath = Joiner.on("/").join("plugins", pluginName);
     this.cfg = cfg;
     this.peerInfoProvider = peerInfoProvider;
     this.gson = gson;
     this.executor = executor;
+    this.metricsRegistry = metricsRegistry;
+    this.executor.onComplete(
+        ev -> {
+          this.metricsRegistry.get(ev.getResult().type()).recordRetries(ev.getAttemptCount());
+        });
   }
 
   @Override
-  public CompletableFuture<Boolean> indexAccount(final int accountId, IndexEvent event) {
-    return execute(RequestMethod.POST, "index account", "index/account", accountId, event);
-  }
-
-  @Override
-  public CompletableFuture<Boolean> indexChange(
-      String projectName, int changeId, IndexEvent event) {
+  public CompletableFuture<Result> indexAccount(final int accountId, IndexEvent event) {
     return execute(
         RequestMethod.POST,
+        EventType.INDEX_ACCOUNT_UPDATE,
+        "index account",
+        "index/account",
+        accountId,
+        event,
+        event.eventCreatedOn);
+  }
+
+  @Override
+  public CompletableFuture<Result> indexChange(String projectName, int changeId, IndexEvent event) {
+    return execute(
+        RequestMethod.POST,
+        EventType.INDEX_CHANGE_UPDATE,
         "index change",
         "index/change",
         buildIndexEndpoint(projectName, changeId),
-        event);
+        event,
+        event.eventCreatedOn);
   }
 
   @Override
-  public CompletableFuture<Boolean> batchIndexChange(
+  public CompletableFuture<Result> batchIndexChange(
       String projectName, int changeId, IndexEvent event) {
     return execute(
         RequestMethod.POST,
+        EventType.INDEX_CHANGE_UPDATE_BATCH,
         "index change",
         "index/change/batch",
         buildIndexEndpoint(projectName, changeId),
-        event);
+        event,
+        event.eventCreatedOn);
   }
 
   @Override
-  public CompletableFuture<Boolean> deleteChangeFromIndex(final int changeId, IndexEvent event) {
+  public CompletableFuture<Result> deleteChangeFromIndex(final int changeId, IndexEvent event) {
     return execute(
-        RequestMethod.DELETE, "delete change", "index/change", buildIndexEndpoint(changeId), event);
+        RequestMethod.DELETE,
+        EventType.INDEX_CHANGE_DELETION,
+        "delete change",
+        "index/change",
+        buildIndexEndpoint(changeId),
+        event,
+        event.eventCreatedOn);
   }
 
   @Override
-  public CompletableFuture<Boolean> indexGroup(final String uuid, IndexEvent event) {
-    return execute(RequestMethod.POST, "index group", "index/group", uuid, event);
+  public CompletableFuture<Result> indexGroup(final String uuid, IndexEvent event) {
+    return execute(
+        RequestMethod.POST,
+        EventType.INDEX_GROUP_UPDATE,
+        "index group",
+        "index/group",
+        uuid,
+        event,
+        event.eventCreatedOn);
   }
 
   private String buildIndexEndpoint(int changeId) {
@@ -126,99 +160,153 @@
   }
 
   @Override
-  public CompletableFuture<Boolean> indexProject(String projectName, IndexEvent event) {
-    return execute(
-        RequestMethod.POST, "index project", "index/project", Url.encode(projectName), event);
-  }
-
-  @Override
-  public CompletableFuture<Boolean> send(final Event event) {
-    return execute(RequestMethod.POST, "send event", "event", event.type, event);
-  }
-
-  @Override
-  public CompletableFuture<Boolean> evict(final String cacheName, final Object key) {
-    String json = gson.toJson(key);
-    return execute(RequestMethod.POST, "invalidate cache " + cacheName, "cache", cacheName, json);
-  }
-
-  @Override
-  public CompletableFuture<Boolean> addToProjectList(String projectName) {
+  public CompletableFuture<Result> indexProject(String projectName, IndexEvent event) {
     return execute(
         RequestMethod.POST,
+        EventType.INDEX_PROJECT_UPDATE,
+        "index project",
+        "index/project",
+        Url.encode(projectName),
+        event,
+        event.eventCreatedOn);
+  }
+
+  @Override
+  public CompletableFuture<Result> send(final Event event) {
+    return execute(
+        RequestMethod.POST,
+        EventType.EVENT_SENT,
+        "send event",
+        "event",
+        event.type,
+        event,
+        Instant.ofEpochSecond(event.eventCreatedOn));
+  }
+
+  @Override
+  public CompletableFuture<Result> evict(final String cacheName, final Object key) {
+    String json = gson.toJson(key);
+    return execute(
+        RequestMethod.POST,
+        EventType.CACHE_EVICTION,
+        "invalidate cache " + cacheName,
+        "cache",
+        cacheName,
+        json,
+        Instant.now());
+  }
+
+  @Override
+  public CompletableFuture<Result> addToProjectList(String projectName) {
+    return execute(
+        RequestMethod.POST,
+        EventType.PROJECT_LIST_ADDITION,
         "Update project_list, add ",
         buildProjectListEndpoint(),
-        Url.encode(projectName));
+        Url.encode(projectName),
+        Instant.now());
   }
 
   @Override
-  public CompletableFuture<Boolean> removeFromProjectList(String projectName) {
+  public CompletableFuture<Result> removeFromProjectList(String projectName) {
     return execute(
         RequestMethod.DELETE,
+        EventType.PROJECT_LIST_DELETION,
         "Update project_list, remove ",
         buildProjectListEndpoint(),
-        Url.encode(projectName));
+        Url.encode(projectName),
+        Instant.now());
   }
 
   @Override
-  public CompletableFuture<Boolean> deleteAllChangesForProject(Project.NameKey projectName) {
+  public CompletableFuture<Result> deleteAllChangesForProject(Project.NameKey projectName) {
     return execute(
         RequestMethod.DELETE,
+        EventType.INDEX_CHANGE_DELETION_ALL_OF_PROJECT,
         "Delete all project changes from index",
         "index/change",
-        buildAllChangesForProjectEndpoint(projectName.get()));
+        buildAllChangesForProjectEndpoint(projectName.get()),
+        Instant.now());
   }
 
   private static String buildProjectListEndpoint() {
     return Joiner.on("/").join("cache", Constants.PROJECT_LIST);
   }
 
-  private CompletableFuture<Boolean> execute(
-      RequestMethod method, String action, String endpoint, Object id) {
-    return execute(method, action, endpoint, id, null);
+  private CompletableFuture<Result> execute(
+      RequestMethod method,
+      EventType eventType,
+      String action,
+      String endpoint,
+      Object id,
+      Instant requestStart) {
+    return execute(method, eventType, action, endpoint, id, null, requestStart);
   }
 
-  private CompletableFuture<Boolean> execute(
-      RequestMethod method, String action, String endpoint, Object id, Object payload) {
+  private CompletableFuture<Result> execute(
+      RequestMethod method,
+      EventType eventType,
+      String action,
+      String endpoint,
+      Object id,
+      Object payload,
+      Instant requestStart) {
+    log.atFine().log("Scheduling forwarding of: %s %s %s", action, id, payload);
     return peerInfoProvider.get().stream()
-        .map(peer -> createRequest(method, peer, action, endpoint, id, payload))
+        .map(
+            peer ->
+                createRequest(method, eventType, peer, action, endpoint, id, payload, requestStart))
         .map(r -> executor.getAsync(() -> r.execute()))
         .reduce(
-            CompletableFuture.completedFuture(true),
-            (a, b) -> a.thenCombine(b, (left, right) -> left && right));
+            CompletableFuture.completedFuture(new Result(eventType, true)),
+            (a, b) ->
+                a.thenCombine(
+                    b, (left, right) -> new Result(eventType, left.result() && right.result())))
+        .thenApplyAsync(
+            result -> {
+              metricsRegistry.get(eventType).recordResult(result.result());
+              metricsRegistry
+                  .get(eventType)
+                  .recordLatency(Duration.between(requestStart, Instant.now()).toMillis());
+              return result;
+            });
   }
 
   private Request createRequest(
       RequestMethod method,
+      EventType eventType,
       PeerInfo peer,
       String action,
       String endpoint,
       Object id,
-      Object payload) {
+      Object payload,
+      Instant createdOn) {
     String destination = peer.getDirectUrl();
-    return new Request(action, id, destination) {
+    return new Request(eventType, action, id, destination) {
       @Override
       HttpResult send() throws IOException {
         String request = Joiner.on("/").join(destination, pluginRelativePath, endpoint, id);
         switch (method) {
           case POST:
-            return httpSession.post(request, payload);
+            return httpSession.post(request, payload, createdOn);
           case DELETE:
           default:
-            return httpSession.delete(request);
+            return httpSession.delete(request, createdOn);
         }
       }
     };
   }
 
   protected abstract class Request {
+    private final EventType eventType;
     private final String action;
     private final Object key;
     private final String destination;
 
     private int execCnt;
 
-    Request(String action, Object key, String destination) {
+    Request(EventType eventType, String action, Object key, String destination) {
+      this.eventType = eventType;
       this.action = action;
       this.key = key;
       this.destination = destination;
@@ -229,13 +317,13 @@
       return String.format("%s:%s => %s (try #%d)", action, key, destination, execCnt);
     }
 
-    boolean execute() throws ForwardingException {
+    Result execute() {
       log.atFine().log("Executing %s %s towards %s", action, key, destination);
       try {
         execCnt++;
         tryOnce();
         log.atFine().log("%s %s towards %s OK", action, key, destination);
-        return true;
+        return new Result(eventType, true);
       } catch (ForwardingException e) {
         int maxTries = cfg.http().maxTries();
         log.atFine().withCause(e).log(
@@ -244,10 +332,10 @@
           log.atSevere().withCause(e).log(
               "%s %s towards %s failed with unrecoverable error; giving up",
               action, key, destination);
-          throw e;
+          return new Result(eventType, false, false);
         }
       }
-      return false;
+      return new Result(eventType, false);
     }
 
     void tryOnce() throws ForwardingException {

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarderModule.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarderModule.java
index 39c9cc0..5d38b16 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarderModule.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarderModule.java

@@ -15,6 +15,7 @@
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder.Result;
 import com.google.inject.AbstractModule;
 import com.google.inject.Scopes;
 import com.google.inject.TypeLiteral;
@@ -29,7 +30,7 @@
     bind(HttpSession.class);
     bind(Forwarder.class).to(RestForwarder.class);
 
-    bind(new TypeLiteral<FailsafeExecutor<Boolean>>() {})
+    bind(new TypeLiteral<FailsafeExecutor<Result>>() {})
         .annotatedWith(RestForwarderExecutor.class)
         .toProvider(FailsafeExecutorProvider.class)
         .in(Scopes.SINGLETON);

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeChecker.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeChecker.java
index 0ed6160..f702d87 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeChecker.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeChecker.java

@@ -17,6 +17,7 @@
 import com.ericsson.gerrit.plugins.highavailability.forwarder.IndexEvent;
 import com.google.gerrit.server.notedb.ChangeNotes;
 import java.io.IOException;
+import java.time.Instant;
 import java.util.Optional;
 
 /** Encapsulates the logic of verifying the up-to-date status of a change. */
@@ -51,8 +52,8 @@
    *
    * <p>Compute the up-to-date Change time-stamp when it is invoked for the very first time.
    *
-   * @return the Change timestamp epoch in seconds
+   * @return the Change timestamp instant
    * @throws IOException if an I/O error occurred while reading the local Change
    */
-  Optional<Long> getComputedChangeTs() throws IOException;
+  Optional<Instant> getComputedChangeTs() throws IOException;
 }

diff --git a/src/main/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeCheckerImpl.java b/src/main/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeCheckerImpl.java
index a392935..6156fb5 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeCheckerImpl.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeCheckerImpl.java

@@ -26,6 +26,7 @@
 import com.google.inject.Inject;
 import com.google.inject.assistedinject.Assisted;
 import java.io.IOException;
+import java.time.Instant;
 import java.util.Objects;
 import java.util.Optional;
 import org.eclipse.jgit.lib.ObjectId;
@@ -38,7 +39,7 @@
   private final OneOffRequestContext oneOffReqCtx;
   private final String changeId;
   private final ChangeFinder changeFinder;
-  private Optional<Long> computedChangeTs = Optional.empty();
+  private Optional<Instant> computedChangeTs = Optional.empty();
   private Optional<ChangeNotes> changeNotes = Optional.empty();
 
   public interface Factory {
@@ -59,12 +60,12 @@
 
   @Override
   public Optional<IndexEvent> newIndexEvent() throws IOException {
-    Optional<Long> changeTs = getComputedChangeTs();
+    Optional<Instant> changeTs = getComputedChangeTs();
     if (!changeTs.isPresent()) {
       return Optional.empty();
     }
 
-    long ts = changeTs.get();
+    Instant ts = changeTs.get();
 
     IndexEvent event = new IndexEvent();
     event.eventCreatedOn = ts;
@@ -99,12 +100,9 @@
       if (indexEventOption.isPresent()) {
         try (Repository repo = gitRepoMgr.openRepository(changeNotes.get().getProjectName())) {
           IndexEvent indexEvent = indexEventOption.get();
-          return (computedChangeTs.get() > indexEvent.eventCreatedOn)
-              || (computedChangeTs.get() == indexEvent.eventCreatedOn)
-                  && (Objects.isNull(indexEvent.targetSha)
-                      || repositoryHas(repo, indexEvent.targetSha))
-                  && (Objects.isNull(indexEvent.targetSha)
-                      || repositoryHas(repo, indexEvent.metaSha));
+          return computedChangeTs.get().compareTo(indexEvent.eventCreatedOn) >= 0
+              && (Objects.isNull(indexEvent.targetSha) || repositoryHas(repo, indexEvent.targetSha))
+              && (Objects.isNull(indexEvent.targetSha) || repositoryHas(repo, indexEvent.metaSha));
         }
       }
       return true;
@@ -116,7 +114,7 @@
   }
 
   @Override
-  public Optional<Long> getComputedChangeTs() {
+  public Optional<Instant> getComputedChangeTs() {
     if (!computedChangeTs.isPresent()) {
       computedChangeTs = computeLastChangeTs();
     }
@@ -166,7 +164,7 @@
     }
   }
 
-  private Optional<Long> computeLastChangeTs() {
+  private Optional<Instant> computeLastChangeTs() {
     return getChangeNotes().map(this::getTsFromChange);
   }
 
@@ -180,8 +178,8 @@
     return ref.getTarget().getObjectId().getName();
   }
 
-  private long getTsFromChange(ChangeNotes notes) {
+  private Instant getTsFromChange(ChangeNotes notes) {
     Change change = notes.getChange();
-    return change.getLastUpdatedOn().toEpochMilli() / 1000;
+    return change.getLastUpdatedOn();
   }
 }

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/CommandDeserializerTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/CommandDeserializerTest.java
index 2f5c5b7..7829a80 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/CommandDeserializerTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/CommandDeserializerTest.java

@@ -17,6 +17,7 @@
 import static com.google.common.truth.Truth.assertThat;
 
 import com.ericsson.gerrit.plugins.highavailability.cache.Constants;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.rest.CacheKeyJsonParser;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.server.events.Event;
@@ -40,7 +41,9 @@
 
   @Test
   public void indexAccount() {
-    Command cmd = gson.fromJson("{type: 'index-account', id: 100}", Command.class);
+    Command cmd =
+        gson.fromJson(
+            String.format("{type: '%s', id: 100}", EventType.INDEX_ACCOUNT_UPDATE), Command.class);
     assertThat(cmd).isInstanceOf(IndexAccount.class);
     IndexAccount index = (IndexAccount) cmd;
     assertThat(index.getId()).isEqualTo(100);
@@ -49,7 +52,10 @@
   @Test
   public void updateChangeCommand() {
     Command cmd =
-        gson.fromJson("{type: 'update-change', projectName: 'foo', id: 100}", Command.class);
+        gson.fromJson(
+            String.format(
+                "{type: '%s', projectName: 'foo', id: 100}", EventType.INDEX_CHANGE_UPDATE),
+            Command.class);
     assertThat(cmd).isInstanceOf(IndexChange.Update.class);
     IndexChange.Update update = (IndexChange.Update) cmd;
     assertThat(update.getId()).isEqualTo("foo~100");
@@ -60,22 +66,30 @@
   public void batchUpdateChangeCommand() {
     Command cmd =
         gson.fromJson(
-            "{type: 'update-change', projectName: 'foo', id: 100, batchMode: 'true'}",
+            String.format(
+                "{type: '%s', projectName: 'foo', id: 100, batchMode: 'true'}",
+                EventType.INDEX_CHANGE_UPDATE_BATCH),
             Command.class);
-    assertThat(cmd).isInstanceOf(IndexChange.Update.class);
-    IndexChange.Update update = (IndexChange.Update) cmd;
+    assertThat(cmd).isInstanceOf(IndexChange.BatchUpdate.class);
+    IndexChange.BatchUpdate update = (IndexChange.BatchUpdate) cmd;
     assertThat(update.getId()).isEqualTo("foo~100");
     assertThat(update.isBatch()).isTrue();
   }
 
   @Test
   public void deleteChangeCommand() {
-    Command cmd = gson.fromJson("{type: 'delete-change', id: 100}", Command.class);
+    Command cmd =
+        gson.fromJson(
+            String.format("{type: '%s', id: 100}", EventType.INDEX_CHANGE_DELETION), Command.class);
     assertThat(cmd).isInstanceOf(IndexChange.Delete.class);
     IndexChange.Delete delete = (IndexChange.Delete) cmd;
     assertThat(delete.getId()).isEqualTo("~100");
 
-    cmd = gson.fromJson("{type: 'delete-change', projectName: 'foo', id: 100}", Command.class);
+    cmd =
+        gson.fromJson(
+            String.format(
+                "{type: '%s', projectName: 'foo', id: 100}", EventType.INDEX_CHANGE_DELETION),
+            Command.class);
     assertThat(cmd).isInstanceOf(IndexChange.Delete.class);
     delete = (IndexChange.Delete) cmd;
     assertThat(delete.getId()).isEqualTo("foo~100");
@@ -83,7 +97,10 @@
 
   @Test
   public void indexGroup() {
-    Command cmd = gson.fromJson("{type: 'index-group', uuid: 'foo'}", Command.class);
+    Command cmd =
+        gson.fromJson(
+            String.format("{type: '%s', uuid: 'foo'}", EventType.INDEX_GROUP_UPDATE),
+            Command.class);
     assertThat(cmd).isInstanceOf(IndexGroup.class);
     IndexGroup index = (IndexGroup) cmd;
     assertThat(index.getUuid()).isEqualTo("foo");
@@ -91,7 +108,10 @@
 
   @Test
   public void indexProject() {
-    Command cmd = gson.fromJson("{type: 'index-project', projectName: 'foo'}", Command.class);
+    Command cmd =
+        gson.fromJson(
+            String.format("{type: '%s', projectName: 'foo'}", EventType.INDEX_PROJECT_UPDATE),
+            Command.class);
     assertThat(cmd).isInstanceOf(IndexProject.class);
     IndexProject index = (IndexProject) cmd;
     assertThat(index.getProjectName()).isEqualTo("foo");
@@ -101,8 +121,10 @@
   public void postEvent() {
     Command cmd =
         gson.fromJson(
-            "{event: {projectName : 'foo', headName : 'refs/heads/master', type :"
-                + " 'project-created', eventCreatedOn:1505898779}, type : 'post-event'}",
+            String.format(
+                "{event: {projectName : 'foo', headName : 'refs/heads/master', type :"
+                    + " 'project-created', eventCreatedOn:1505898779}, type : '%s'}",
+                EventType.EVENT_SENT),
             Command.class);
     assertThat(cmd).isInstanceOf(PostEvent.class);
     Event e = ((PostEvent) cmd).getEvent();
@@ -118,7 +140,7 @@
         gson.fromJson(
             String.format(
                 "{type: '%s', cacheName: '%s', keyJson: '%s'}",
-                EvictCache.TYPE, Constants.PROJECTS, keyJson),
+                EventType.CACHE_EVICTION, Constants.PROJECTS, keyJson),
             EvictCache.class);
     assertThat(cmd).isInstanceOf(EvictCache.class);
     EvictCache evict = (EvictCache) cmd;
@@ -130,7 +152,10 @@
 
   @Test
   public void addToProjectList() {
-    Command cmd = gson.fromJson("{type: 'add-to-project-list', projectName: 'foo'}", Command.class);
+    Command cmd =
+        gson.fromJson(
+            String.format("{type: '%s', projectName: 'foo'}", EventType.PROJECT_LIST_ADDITION),
+            Command.class);
     assertThat(cmd).isInstanceOf(AddToProjectList.class);
     AddToProjectList addToProjectList = (AddToProjectList) cmd;
     assertThat(addToProjectList.getProjectName()).isEqualTo("foo");
@@ -139,7 +164,9 @@
   @Test
   public void removeFromProjectList() {
     Command cmd =
-        gson.fromJson("{type: 'remove-from-project-list', projectName: 'foo'}", Command.class);
+        gson.fromJson(
+            String.format("{type: '%s', projectName: 'foo'}", EventType.PROJECT_LIST_DELETION),
+            Command.class);
     assertThat(cmd).isInstanceOf(RemoveFromProjectList.class);
     RemoveFromProjectList removeFromProjectList = (RemoveFromProjectList) cmd;
     assertThat(removeFromProjectList.getProjectName()).isEqualTo("foo");

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarderTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarderTest.java
index 082b5d1..e7542b4 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarderTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/JGroupsForwarderTest.java

@@ -23,6 +23,10 @@
 import static org.mockito.Mockito.when;
 
 import com.ericsson.gerrit.plugins.highavailability.Configuration;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder.Result;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwarderMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwarderMetricsRegistry;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.IndexEvent;
 import com.google.gerrit.server.events.EventGsonProvider;
 import com.google.gerrit.server.git.WorkQueue;
 import com.google.gson.Gson;
@@ -30,7 +34,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import org.jgroups.Address;
 import org.jgroups.blocks.MessageDispatcher;
 import org.jgroups.util.Rsp;
@@ -38,7 +42,10 @@
 import org.jgroups.util.UUID;
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
 
+@RunWith(org.mockito.junit.MockitoJUnitRunner.class)
 public class JGroupsForwarderTest {
 
   private static final int MAX_TRIES = 3;
@@ -52,6 +59,9 @@
   private MessageDispatcher dispatcher;
   private JGroupsForwarder forwarder;
 
+  @Mock ForwarderMetricsRegistry metricsRegistry;
+  @Mock ForwarderMetrics metrics;
+
   @Before
   public void setUp() throws Exception {
     Gson eventGson = new EventGsonProvider().get();
@@ -67,10 +77,17 @@
 
     WorkQueue workQueue = mock(WorkQueue.class);
     when(workQueue.createQueue(THREAD_POOLS_SIZE, "JGroupsForwarder"))
-        .thenReturn(Executors.newScheduledThreadPool(THREAD_POOLS_SIZE));
+        .thenReturn(new ScheduledThreadPoolExecutor(THREAD_POOLS_SIZE));
+
+    when(metricsRegistry.get(any())).thenReturn(metrics);
+
     forwarder =
         new JGroupsForwarder(
-            dispatcher, cfg, gson, new FailsafeExecutorProvider(cfg, workQueue).get());
+            dispatcher,
+            cfg,
+            gson,
+            new FailsafeExecutorProvider(cfg, workQueue).get(),
+            metricsRegistry);
   }
 
   @Test
@@ -78,8 +95,8 @@
     RspList<Object> OK = new RspList<>(Map.of(A1, RSP_OK, A2, RSP_OK));
     when(dispatcher.castMessage(any(), any(), any())).thenReturn(OK);
 
-    CompletableFuture<Boolean> result = forwarder.indexAccount(100, null);
-    assertThat(result.get()).isTrue();
+    CompletableFuture<Result> result = forwarder.indexAccount(100, new IndexEvent());
+    assertThat(result.get().result()).isTrue();
     verify(dispatcher, times(1)).castMessage(any(), any(), any());
   }
 
@@ -90,8 +107,8 @@
     RspList<Object> FAIL = new RspList<>(Map.of(A1, RSP_OK, A2, RSP_FAIL));
     when(dispatcher.castMessage(any(), any(), any())).thenReturn(FAIL, OK);
 
-    CompletableFuture<Boolean> result = forwarder.indexAccount(100, null);
-    assertThat(result.get()).isTrue();
+    CompletableFuture<Result> result = forwarder.indexAccount(100, new IndexEvent());
+    assertThat(result.get().result()).isTrue();
     verify(dispatcher, times(2)).castMessage(any(), any(), any());
   }
 
@@ -102,8 +119,8 @@
     // return FAIL x MAX_TRIES
     when(dispatcher.castMessage(any(), any(), any())).thenReturn(FAIL, FAIL, FAIL);
 
-    CompletableFuture<Boolean> result = forwarder.indexAccount(100, null);
-    assertThat(result.get()).isFalse();
+    CompletableFuture<Result> result = forwarder.indexAccount(100, new IndexEvent());
+    assertThat(result.get().result()).isFalse();
     verify(dispatcher, times(MAX_TRIES)).castMessage(any(), any(), any());
   }
 }

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/MessageProcessorTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/MessageProcessorTest.java
index c3114de..91d291c 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/MessageProcessorTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/jgroups/MessageProcessorTest.java

@@ -15,10 +15,12 @@
 package com.ericsson.gerrit.plugins.highavailability.forwarder.jgroups;
 
 import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyNoInteractions;
+import static org.mockito.Mockito.when;
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.CacheEntry;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.CacheNotFoundException;
@@ -29,6 +31,8 @@
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexChangeHandler;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexingHandler.Operation;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedProjectListUpdateHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.server.events.Event;
@@ -37,14 +41,18 @@
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gson.Gson;
 import java.io.IOException;
+import java.time.Instant;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 import org.jgroups.ObjectMessage;
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
+import org.mockito.Mock;
 
+@RunWith(org.mockito.junit.MockitoJUnitRunner.class)
 public class MessageProcessorTest {
 
   private MessageProcessor processor;
@@ -57,10 +65,14 @@
   private ForwardedEventHandler eventHandler;
   private ForwardedProjectListUpdateHandler projectListUpdateHandler;
 
+  @Mock ProcessorMetrics processorMetrics;
+  @Mock ProcessorMetricsRegistry metricsRegistry;
+
   private List<Object> allHandlers = new ArrayList<>();
 
   @Before
   public void setUp() {
+    when(metricsRegistry.get(any())).thenReturn(processorMetrics);
     Gson eventGson = new EventGsonProvider().get();
     gson = new JGroupsForwarderModule().buildJGroupsGson(eventGson);
 
@@ -79,7 +91,8 @@
             indexAccountHandler,
             cacheEvictionHandler,
             eventHandler,
-            projectListUpdateHandler);
+            projectListUpdateHandler,
+            metricsRegistry);
   }
 
   private <T> T createHandlerMock(Class<T> handlerClass) {
@@ -92,7 +105,7 @@
   public void indexAccount() throws IOException {
     int ACCOUNT_ID = 100;
 
-    IndexAccount cmd = new IndexAccount(ACCOUNT_ID);
+    IndexAccount cmd = new IndexAccount(ACCOUNT_ID, Instant.now());
     assertThat(processor.handle(new ObjectMessage(null, gson.toJson(cmd)))).isEqualTo(true);
     verify(indexAccountHandler, times(1))
         .index(Account.id(ACCOUNT_ID), Operation.INDEX, Optional.empty());
@@ -104,7 +117,7 @@
     String PROJECT = "foo";
     int CHANGE_ID = 100;
 
-    IndexChange.Update cmd = new IndexChange.Update(PROJECT, CHANGE_ID);
+    IndexChange.Update cmd = new IndexChange.Update(PROJECT, CHANGE_ID, Instant.now());
     assertThat(processor.handle(new ObjectMessage(null, gson.toJson(cmd)))).isEqualTo(true);
     verify(indexChangeHandler, times(1))
         .index(PROJECT + "~" + Change.id(CHANGE_ID), Operation.INDEX, Optional.empty());
@@ -116,7 +129,7 @@
     String PROJECT = "foo";
     int CHANGE_ID = 100;
 
-    IndexChange.Update cmd = new IndexChange.Update(PROJECT, CHANGE_ID, true);
+    IndexChange.BatchUpdate cmd = new IndexChange.BatchUpdate(PROJECT, CHANGE_ID, Instant.now());
     assertThat(processor.handle(new ObjectMessage(null, gson.toJson(cmd)))).isEqualTo(true);
     verify(indexBatchChangeHandler, times(1))
         .index(PROJECT + "~" + Change.id(CHANGE_ID), Operation.INDEX, Optional.empty());
@@ -128,7 +141,7 @@
     String PROJECT = "foo";
     int CHANGE_ID = 100;
 
-    IndexChange.Delete cmd = new IndexChange.Delete(PROJECT, CHANGE_ID);
+    IndexChange.Delete cmd = new IndexChange.Delete(PROJECT, CHANGE_ID, Instant.now());
     assertThat(processor.handle(new ObjectMessage(null, gson.toJson(cmd)))).isEqualTo(true);
     verify(indexChangeHandler, times(1))
         .index(PROJECT + "~" + Change.id(CHANGE_ID), Operation.DELETE, Optional.empty());
@@ -140,7 +153,7 @@
     String CACHE = "foo";
     String KEY_JSON = gson.toJson(100);
 
-    EvictCache cmd = new EvictCache(CACHE, KEY_JSON);
+    EvictCache cmd = new EvictCache(CACHE, KEY_JSON, Instant.now());
     assertThat(processor.handle(new ObjectMessage(null, gson.toJson(cmd)))).isEqualTo(true);
     CacheEntry e = CacheEntry.from(CACHE, KEY_JSON);
     verify(cacheEvictionHandler, times(1)).evict(e);
@@ -154,7 +167,7 @@
 
     EventTypes.register(TestEvent.TYPE, TestEvent.class);
     TestEvent event = new TestEvent(FOO, BAR);
-    PostEvent cmd = new PostEvent(event);
+    PostEvent cmd = new PostEvent(event, Instant.now());
     assertThat(processor.handle(new ObjectMessage(null, gson.toJson(cmd)))).isEqualTo(true);
     ArgumentCaptor<Event> captor = ArgumentCaptor.forClass(Event.class);
     verify(eventHandler, times(1)).dispatch(captor.capture());
@@ -169,7 +182,7 @@
   public void addToProjectList() throws IOException {
     String PROJECT = "foo";
 
-    AddToProjectList cmd = new AddToProjectList(PROJECT);
+    AddToProjectList cmd = new AddToProjectList(PROJECT, Instant.now());
     assertThat(processor.handle(new ObjectMessage(null, gson.toJson(cmd)))).isEqualTo(true);
     verify(projectListUpdateHandler, times(1)).update(PROJECT, false);
     verifyOtherHandlersNotUsed(projectListUpdateHandler);
@@ -179,7 +192,7 @@
   public void removeFromProjectList() throws IOException {
     String PROJECT = "foo";
 
-    RemoveFromProjectList cmd = new RemoveFromProjectList(PROJECT);
+    RemoveFromProjectList cmd = new RemoveFromProjectList(PROJECT, Instant.now());
     assertThat(processor.handle(new ObjectMessage(null, gson.toJson(cmd)))).isEqualTo(true);
     verify(projectListUpdateHandler, times(1)).update(PROJECT, true);
     verifyOtherHandlersNotUsed(projectListUpdateHandler);

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheRestApiServletTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheRestApiServletTest.java
index 58c0aef..68d348c 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheRestApiServletTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/CacheRestApiServletTest.java

@@ -24,6 +24,8 @@
 import com.ericsson.gerrit.plugins.highavailability.cache.Constants;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.CacheNotFoundException;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedCacheEvictionHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gson.Gson;
 import java.io.BufferedReader;
 import java.io.IOException;
@@ -41,13 +43,16 @@
   @Mock private HttpServletResponse responseMock;
   @Mock private BufferedReader readerMock;
   @Mock private ForwardedCacheEvictionHandler forwardedCacheEvictionHandlerMock;
+  @Mock private ProcessorMetricsRegistry metricsRegistry;
+  @Mock ProcessorMetrics metrics;
   private CacheRestApiServlet servlet;
 
   @Before
   public void setUp() {
+    when(metricsRegistry.get(any())).thenReturn(metrics);
     servlet =
         new CacheRestApiServlet(
-            forwardedCacheEvictionHandlerMock, new CacheKeyJsonParser(new Gson()));
+            forwardedCacheEvictionHandlerMock, new CacheKeyJsonParser(new Gson()), metricsRegistry);
   }
 
   @Test

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/EventRestApiServletTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/EventRestApiServletTest.java
index 7c23e29..9ed764f 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/EventRestApiServletTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/EventRestApiServletTest.java

@@ -24,6 +24,8 @@
 import static org.mockito.Mockito.when;
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedEventHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.common.net.MediaType;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.server.events.EventDispatcher;
@@ -52,6 +54,8 @@
   @Mock private ForwardedEventHandler forwardedEventHandlerMock;
   @Mock private HttpServletRequest requestMock;
   @Mock private HttpServletResponse responseMock;
+  @Mock private ProcessorMetricsRegistry metricsRegistryMock;
+  @Mock private ProcessorMetrics metrics;
   private EventRestApiServlet eventRestApiServlet;
   private Gson gson = new EventGsonProvider().get();
 
@@ -62,7 +66,9 @@
 
   @Before
   public void createEventsRestApiServlet() throws Exception {
-    eventRestApiServlet = new EventRestApiServlet(forwardedEventHandlerMock, gson);
+    when(metricsRegistryMock.get(any())).thenReturn(metrics);
+    eventRestApiServlet =
+        new EventRestApiServlet(forwardedEventHandlerMock, gson, metricsRegistryMock);
     when(requestMock.getContentType()).thenReturn(MediaType.JSON_UTF_8.toString());
   }
 
@@ -93,7 +99,7 @@
         .when(dispatcher)
         .postEvent(any(RefReplicationDoneEvent.class));
     ForwardedEventHandler forwardedEventHandler = new ForwardedEventHandler(dispatcher);
-    eventRestApiServlet = new EventRestApiServlet(forwardedEventHandler, gson);
+    eventRestApiServlet = new EventRestApiServlet(forwardedEventHandler, gson, metricsRegistryMock);
     eventRestApiServlet.doPost(requestMock, responseMock);
     verify(responseMock).setStatus(SC_NO_CONTENT);
   }

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ForwardedCacheEvictionHandlerIT.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ForwardedCacheEvictionHandlerIT.java
index 5a0833f..3df6104 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ForwardedCacheEvictionHandlerIT.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ForwardedCacheEvictionHandlerIT.java

@@ -16,8 +16,6 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
-import com.ericsson.gerrit.plugins.highavailability.forwarder.CacheEntry;
-import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedCacheEvictionHandler;
 import com.google.common.cache.RemovalNotification;
 import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
@@ -39,8 +37,6 @@
 import org.junit.Before;
 import org.junit.Test;
 
-@NoHttpd
-@UseSsh
 @TestPlugin(
     name = "high-availability",
     sysModule = "com.ericsson.gerrit.plugins.highavailability.Module",
@@ -53,8 +49,6 @@
   private DynamicSet<CacheRemovalListener> cacheRemovalListeners;
 
   @Inject @EventGson private Gson gson;
-  @Inject private ForwardedCacheEvictionHandler objectUnderTest;
-  @Inject private CacheKeyJsonParser gsonParser;
 
   private CacheEvictionsTracker<?, ?> evictionsCacheTracker;
   private RegistrationHandle cacheEvictionRegistrationHandle;
@@ -106,8 +100,10 @@
 
   @Test
   public void shouldEvictProjectCache() throws Exception {
-    Object parsedKey = gsonParser.fromJson(ProjectCacheImpl.CACHE_NAME, gson.toJson(project));
-    objectUnderTest.evict(CacheEntry.from(ProjectCacheImpl.CACHE_NAME, parsedKey));
+    adminRestSession
+        .post(
+            "/plugins/high-availability/cache/" + ProjectCacheImpl.CACHE_NAME, gson.toJson(project))
+        .assertNoContent();
     evictionsCacheTracker.waitForExpectedEvictions();
 
     assertThat(evictionsCacheTracker.trackedEvictionsFor(ProjectCacheImpl.CACHE_NAME))

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/HttpSessionTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/HttpSessionTest.java
index 4d874dd..a0bcf10 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/HttpSessionTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/HttpSessionTest.java

@@ -31,6 +31,7 @@
 import com.google.gson.Gson;
 import java.net.SocketTimeoutException;
 import java.time.Duration;
+import java.time.Instant;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
@@ -80,7 +81,7 @@
     wireMockRule.givenThat(
         post(urlEqualTo(ENDPOINT)).willReturn(aResponse().withStatus(NO_CONTENT)));
 
-    assertThat(httpSession.post(uri).isSuccessful()).isTrue();
+    assertThat(httpSession.post(uri, Instant.now()).isSuccessful()).isTrue();
   }
 
   @Test
@@ -89,7 +90,7 @@
         post(urlEqualTo(ENDPOINT))
             .withRequestBody(equalTo(BODY))
             .willReturn(aResponse().withStatus(NO_CONTENT)));
-    assertThat(httpSession.post(uri, BODY).isSuccessful()).isTrue();
+    assertThat(httpSession.post(uri, BODY, Instant.now()).isSuccessful()).isTrue();
   }
 
   @Test
@@ -97,7 +98,7 @@
     wireMockRule.givenThat(
         delete(urlEqualTo(ENDPOINT)).willReturn(aResponse().withStatus(NO_CONTENT)));
 
-    assertThat(httpSession.delete(uri).isSuccessful()).isTrue();
+    assertThat(httpSession.delete(uri, Instant.now()).isSuccessful()).isTrue();
   }
 
   @Test
@@ -107,7 +108,7 @@
         post(urlEqualTo(ENDPOINT))
             .willReturn(aResponse().withStatus(UNAUTHORIZED).withBody(expected)));
 
-    HttpResult result = httpSession.post(uri);
+    HttpResult result = httpSession.post(uri, Instant.now());
     assertThat(result.isSuccessful()).isFalse();
     assertThat(result.getMessage()).isEqualTo(expected);
   }
@@ -119,7 +120,7 @@
         post(urlEqualTo(ENDPOINT))
             .willReturn(aResponse().withStatus(NOT_FOUND).withBody(expected)));
 
-    HttpResult result = httpSession.post(uri);
+    HttpResult result = httpSession.post(uri, Instant.now());
     assertThat(result.isSuccessful()).isFalse();
     assertThat(result.getMessage()).isEqualTo(expected);
   }
@@ -130,7 +131,7 @@
         post(urlEqualTo(ENDPOINT))
             .willReturn(aResponse().withStatus(ERROR).withBody(ERROR_MESSAGE)));
 
-    HttpResult result = httpSession.post(uri);
+    HttpResult result = httpSession.post(uri, Instant.now());
     assertThat(result.isSuccessful()).isFalse();
     assertThat(result.getMessage()).isEqualTo(ERROR_MESSAGE);
   }
@@ -161,7 +162,7 @@
             .whenScenarioStateIs(THIRD_TRY)
             .willReturn(aResponse().withFixedDelay((int) TIMEOUT.toMillis())));
 
-    httpSession.post(uri);
+    httpSession.post(uri, Instant.now());
   }
 
   @Test
@@ -170,6 +171,6 @@
         post(urlEqualTo(ENDPOINT))
             .willReturn(aResponse().withFault(Fault.MALFORMED_RESPONSE_CHUNK)));
 
-    assertThat(httpSession.post(uri).isSuccessful()).isFalse();
+    assertThat(httpSession.post(uri, Instant.now()).isSuccessful()).isFalse();
   }
 }

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexAccountRestApiServletTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexAccountRestApiServletTest.java
index 83102a9..49ce5f8 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexAccountRestApiServletTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexAccountRestApiServletTest.java

@@ -26,7 +26,10 @@
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexAccountHandler;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexingHandler.Operation;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.entities.Account;
+import com.google.gson.Gson;
 import java.io.IOException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
@@ -44,13 +47,16 @@
   @Mock private ForwardedIndexAccountHandler handlerMock;
   @Mock private HttpServletRequest requestMock;
   @Mock private HttpServletResponse responseMock;
+  @Mock private ProcessorMetricsRegistry metricsRegistryMock;
+  @Mock private ProcessorMetrics metrics;
 
   private Account.Id id;
   private IndexAccountRestApiServlet servlet;
 
   @Before
   public void setUpMocks() {
-    servlet = new IndexAccountRestApiServlet(handlerMock);
+    when(metricsRegistryMock.get(any())).thenReturn(metrics);
+    servlet = new IndexAccountRestApiServlet(handlerMock, new Gson(), metricsRegistryMock);
     id = Account.id(ACCOUNT_NUMBER);
     when(requestMock.getRequestURI())
         .thenReturn("http://gerrit.com/index/account/" + ACCOUNT_NUMBER);

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexChangeRestApiServletTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexChangeRestApiServletTest.java
index 3da35d4..a19fda6 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexChangeRestApiServletTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexChangeRestApiServletTest.java

@@ -25,6 +25,8 @@
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexChangeHandler;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexingHandler.Operation;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gson.Gson;
 import java.io.IOException;
 import javax.servlet.http.HttpServletRequest;
@@ -46,12 +48,15 @@
   @Mock private ForwardedIndexChangeHandler handlerMock;
   @Mock private HttpServletRequest requestMock;
   @Mock private HttpServletResponse responseMock;
+  @Mock private ProcessorMetricsRegistry metricsRegistryMock;
+  @Mock private ProcessorMetrics metrics;
 
   private IndexChangeRestApiServlet servlet;
 
   @Before
   public void setUpMocks() {
-    servlet = new IndexChangeRestApiServlet(handlerMock, new Gson());
+    when(metricsRegistryMock.get(any())).thenReturn(metrics);
+    servlet = new IndexChangeRestApiServlet(handlerMock, new Gson(), metricsRegistryMock);
     when(requestMock.getRequestURI())
         .thenReturn("http://gerrit.com/index/change/" + PROJECT_NAME_URL_ENC + "~" + CHANGE_NUMBER);
   }

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexGroupRestApiServletTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexGroupRestApiServletTest.java
index fb5788d..0e87bf7 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexGroupRestApiServletTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexGroupRestApiServletTest.java

@@ -26,7 +26,10 @@
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexGroupHandler;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexingHandler.Operation;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.entities.AccountGroup;
+import com.google.gson.Gson;
 import java.io.IOException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
@@ -44,13 +47,16 @@
   @Mock private ForwardedIndexGroupHandler handlerMock;
   @Mock private HttpServletRequest requestMock;
   @Mock private HttpServletResponse responseMock;
+  @Mock private ProcessorMetricsRegistry metricsRegistryMock;
+  @Mock private ProcessorMetrics metrics;
 
   private AccountGroup.UUID uuid;
   private IndexGroupRestApiServlet servlet;
 
   @Before
   public void setUpMocks() {
-    servlet = new IndexGroupRestApiServlet(handlerMock);
+    when(metricsRegistryMock.get(any())).thenReturn(metrics);
+    servlet = new IndexGroupRestApiServlet(handlerMock, new Gson(), metricsRegistryMock);
     uuid = AccountGroup.uuid(UUID);
     when(requestMock.getRequestURI()).thenReturn("http://gerrit.com/index/group/" + UUID);
   }

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexProjectRestApiServletTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexProjectRestApiServletTest.java
index da6e70d..d74a43f 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexProjectRestApiServletTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/IndexProjectRestApiServletTest.java

@@ -26,8 +26,11 @@
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexProjectHandler;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedIndexingHandler.Operation;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.restapi.Url;
+import com.google.gson.Gson;
 import java.io.IOException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
@@ -45,13 +48,16 @@
   @Mock private ForwardedIndexProjectHandler handlerMock;
   @Mock private HttpServletRequest requestMock;
   @Mock private HttpServletResponse responseMock;
+  @Mock private ProcessorMetricsRegistry metricsRegistryMock;
+  @Mock private ProcessorMetrics metrics;
 
   private Project.NameKey nameKey;
   private IndexProjectRestApiServlet servlet;
 
   @Before
   public void setUpMocks() {
-    servlet = new IndexProjectRestApiServlet(handlerMock);
+    when(metricsRegistryMock.get(any())).thenReturn(metrics);
+    servlet = new IndexProjectRestApiServlet(handlerMock, new Gson(), metricsRegistryMock);
     nameKey = Project.nameKey(PROJECT_NAME);
     when(requestMock.getRequestURI())
         .thenReturn("http://gerrit.com/index/project/" + Url.encode(nameKey.get()));

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ProjectListRestApiServletTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ProjectListRestApiServletTest.java
index 38ab488..fd0813e 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ProjectListRestApiServletTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/ProjectListRestApiServletTest.java

@@ -15,11 +15,14 @@
 package com.ericsson.gerrit.plugins.highavailability.forwarder.rest;
 
 import static javax.servlet.http.HttpServletResponse.SC_NO_CONTENT;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwardedProjectListUpdateHandler;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ProcessorMetricsRegistry;
 import com.google.gerrit.extensions.restapi.Url;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
@@ -36,12 +39,15 @@
   @Mock private ForwardedProjectListUpdateHandler handlerMock;
   @Mock private HttpServletRequest requestMock;
   @Mock private HttpServletResponse responseMock;
+  @Mock private ProcessorMetricsRegistry metricsRegistryMock;
+  @Mock private ProcessorMetrics metrics;
 
   private ProjectListApiServlet servlet;
 
   @Before
   public void setUpMocks() {
-    servlet = new ProjectListApiServlet(handlerMock);
+    when(metricsRegistryMock.get(any())).thenReturn(metrics);
+    servlet = new ProjectListApiServlet(handlerMock, metricsRegistryMock);
     when(requestMock.getRequestURI())
         .thenReturn(
             "http://hostname/plugins/high-availability/cache/project_list/"

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarderTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarderTest.java
index 4b98fe1..78d21ef 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarderTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/forwarder/rest/RestForwarderTest.java

@@ -19,12 +19,13 @@
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
-import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
 import com.ericsson.gerrit.plugins.highavailability.Configuration;
 import com.ericsson.gerrit.plugins.highavailability.cache.Constants;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwarderMetrics;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.ForwarderMetricsRegistry;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.IndexEvent;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.TestEvent;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.rest.HttpResponseHandler.HttpResult;
@@ -35,19 +36,20 @@
 import com.google.gerrit.entities.AccountGroup;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.server.events.Event;
-import com.google.gerrit.server.git.WorkQueue;
 import com.google.gson.Gson;
 import com.google.inject.Provider;
 import java.io.IOException;
 import java.time.Duration;
 import java.util.Set;
-import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import javax.net.ssl.SSLException;
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.runner.RunWith;
 import org.mockito.Answers;
+import org.mockito.Mock;
 
+@RunWith(org.mockito.junit.MockitoJUnitRunner.class)
 public class RestForwarderTest {
   private static final String URL = "http://fake.com";
   private static final String PLUGIN_NAME = "high-availability";
@@ -111,6 +113,9 @@
   private Configuration configMock;
   Provider<Set<PeerInfo>> peersMock;
 
+  @Mock ForwarderMetricsRegistry metricsRegistry;
+  @Mock ForwarderMetrics metrics;
+
   @SuppressWarnings("unchecked")
   @Before
   public void setUp() {
@@ -121,9 +126,7 @@
     when(configMock.http().threadPoolSize()).thenReturn(2);
     peersMock = mock(Provider.class);
     when(peersMock.get()).thenReturn(ImmutableSet.of(new PeerInfo(URL)));
-    WorkQueue workQueue = mock(WorkQueue.class);
-    when(workQueue.createQueue(configMock.http().threadPoolSize(), "RestForwarderScheduler"))
-        .thenReturn(Executors.newScheduledThreadPool(2));
+    when(metricsRegistry.get(any())).thenReturn(metrics);
     forwarder =
         new RestForwarder(
             httpSessionMock,
@@ -131,188 +134,228 @@
             configMock,
             peersMock,
             gson, // TODO: Create provider
-            new FailsafeExecutorProvider(configMock).get());
+            new FailsafeExecutorProvider(configMock).get(),
+            metricsRegistry);
   }
 
   @Test
   public void testIndexAccountOK() throws Exception {
-    when(httpSessionMock.post(eq(INDEX_ACCOUNT_ENDPOINT), any()))
+    when(httpSessionMock.post(eq(INDEX_ACCOUNT_ENDPOINT), any(), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
     assertThat(
             forwarder
                 .indexAccount(ACCOUNT_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
   @Test
   public void testIndexAccountFailed() throws Exception {
-    when(httpSessionMock.post(eq(INDEX_ACCOUNT_ENDPOINT), any()))
+    when(httpSessionMock.post(eq(INDEX_ACCOUNT_ENDPOINT), any(), any()))
         .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
     assertThat(
             forwarder
                 .indexAccount(ACCOUNT_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testIndexAccountThrowsException() throws Exception {
-    doThrow(new IOException()).when(httpSessionMock).post(eq(INDEX_ACCOUNT_ENDPOINT), any());
+    when(httpSessionMock.post(eq(INDEX_ACCOUNT_ENDPOINT), any(), any()))
+        .thenThrow(IOException.class);
     assertThat(
             forwarder
                 .indexAccount(ACCOUNT_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testIndexGroupOK() throws Exception {
-    when(httpSessionMock.post(eq(INDEX_GROUP_ENDPOINT), any()))
+    when(httpSessionMock.post(eq(INDEX_GROUP_ENDPOINT), any(), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.indexGroup(UUID, new IndexEvent()).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder
+                .indexGroup(UUID, new IndexEvent())
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
   @Test
   public void testIndexGroupFailed() throws Exception {
-    when(httpSessionMock.post(eq(INDEX_GROUP_ENDPOINT), any()))
+    when(httpSessionMock.post(eq(INDEX_GROUP_ENDPOINT), any(), any()))
         .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
-    assertThat(forwarder.indexGroup(UUID, new IndexEvent()).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder
+                .indexGroup(UUID, new IndexEvent())
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testIndexGroupThrowsException() throws Exception {
-    doThrow(new IOException()).when(httpSessionMock).post(eq(INDEX_GROUP_ENDPOINT), any());
-    assertThat(forwarder.indexGroup(UUID, new IndexEvent()).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    when(httpSessionMock.post(eq(INDEX_GROUP_ENDPOINT), any(), any())).thenThrow(IOException.class);
+    assertThat(
+            forwarder
+                .indexGroup(UUID, new IndexEvent())
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testIndexChangeOK() throws Exception {
-    when(httpSessionMock.post(eq(INDEX_CHANGE_ENDPOINT), any()))
+    when(httpSessionMock.post(eq(INDEX_CHANGE_ENDPOINT), any(), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
     assertThat(
             forwarder
                 .indexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
   @Test
   public void testIndexChangeFailed() throws Exception {
-    when(httpSessionMock.post(eq(INDEX_CHANGE_ENDPOINT), any()))
+    when(httpSessionMock.post(eq(INDEX_CHANGE_ENDPOINT), any(), any()))
         .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
     assertThat(
             forwarder
                 .indexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testIndexChangeThrowsException() throws Exception {
-    doThrow(new IOException()).when(httpSessionMock).post(eq(INDEX_CHANGE_ENDPOINT), any());
+    when(httpSessionMock.post(eq(INDEX_CHANGE_ENDPOINT), any(), any()))
+        .thenThrow(IOException.class);
     assertThat(
             forwarder
                 .indexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testIndexBatchChangeOK() throws Exception {
-    when(httpSessionMock.post(eq(INDEX_BATCH_CHANGE_ENDPOINT), any()))
+    when(httpSessionMock.post(eq(INDEX_BATCH_CHANGE_ENDPOINT), any(), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.batchIndexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent()).get())
+    assertThat(
+            forwarder
+                .batchIndexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent())
+                .get()
+                .result())
         .isTrue();
   }
 
   @Test
   public void testIndexBatchChangeFailed() throws Exception {
-    when(httpSessionMock.post(eq(INDEX_BATCH_CHANGE_ENDPOINT), any()))
+    when(httpSessionMock.post(eq(INDEX_BATCH_CHANGE_ENDPOINT), any(), any()))
         .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
-    assertThat(forwarder.batchIndexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent()).get())
+    assertThat(
+            forwarder
+                .batchIndexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent())
+                .get()
+                .result())
         .isFalse();
   }
 
   @Test
   public void testIndexBatchChangeThrowsException() throws Exception {
-    doThrow(new IOException()).when(httpSessionMock).post(eq(INDEX_BATCH_CHANGE_ENDPOINT), any());
-    assertThat(forwarder.batchIndexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent()).get())
+    when(httpSessionMock.post(eq(INDEX_BATCH_CHANGE_ENDPOINT), any(), any()))
+        .thenThrow(IOException.class);
+    assertThat(
+            forwarder
+                .batchIndexChange(PROJECT_NAME, CHANGE_NUMBER, new IndexEvent())
+                .get()
+                .result())
         .isFalse();
   }
 
   @Test
   public void testChangeDeletedFromIndexOK() throws Exception {
-    when(httpSessionMock.delete(eq(DELETE_CHANGE_ENDPOINT)))
+    when(httpSessionMock.delete(eq(DELETE_CHANGE_ENDPOINT), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
     assertThat(
             forwarder
                 .deleteChangeFromIndex(CHANGE_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
   @Test
   public void testAllChangesDeletedFromIndexOK() throws Exception {
-    when(httpSessionMock.delete(eq(DELETE_ALL_CHANGES_ENDPOINT)))
+    when(httpSessionMock.delete(eq(DELETE_ALL_CHANGES_ENDPOINT), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
     assertThat(
             forwarder
                 .deleteAllChangesForProject(Project.nameKey(PROJECT_NAME))
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
   @Test
   public void testChangeDeletedFromIndexFailed() throws Exception {
-    when(httpSessionMock.delete(eq(DELETE_CHANGE_ENDPOINT)))
+    when(httpSessionMock.delete(eq(DELETE_CHANGE_ENDPOINT), any()))
         .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
     assertThat(
             forwarder
                 .deleteChangeFromIndex(CHANGE_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testChangeDeletedFromThrowsException() throws Exception {
-    doThrow(new IOException()).when(httpSessionMock).delete(eq(DELETE_CHANGE_ENDPOINT));
+    when(httpSessionMock.delete(eq(DELETE_CHANGE_ENDPOINT), any())).thenThrow(IOException.class);
     assertThat(
             forwarder
                 .deleteChangeFromIndex(CHANGE_NUMBER, new IndexEvent())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testEventSentOK() throws Exception {
-    when(httpSessionMock.post(EVENT_ENDPOINT, event))
+    when(httpSessionMock.post(eq(EVENT_ENDPOINT), eq(event), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.send(event).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)).isTrue();
+    assertThat(forwarder.send(event).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result()).isTrue();
   }
 
   @Test
   public void testEventSentFailed() throws Exception {
-    when(httpSessionMock.post(EVENT_ENDPOINT, event)).thenReturn(new HttpResult(FAILED, EMPTY_MSG));
-    assertThat(forwarder.send(event).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)).isFalse();
+    when(httpSessionMock.post(eq(EVENT_ENDPOINT), eq(event), any()))
+        .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
+    assertThat(forwarder.send(event).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result()).isFalse();
   }
 
   @Test
   public void testEventSentThrowsException() throws Exception {
-    doThrow(new IOException()).when(httpSessionMock).post(EVENT_ENDPOINT, event);
-    assertThat(forwarder.send(event).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)).isFalse();
+    when(httpSessionMock.post(eq(EVENT_ENDPOINT), eq(event), any())).thenThrow(IOException.class);
+    assertThat(forwarder.send(event).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result()).isFalse();
   }
 
   @Test
   public void testEvictProjectOK() throws Exception {
     String key = PROJECT_NAME;
     String keyJson = gson.toJson(key);
-    when(httpSessionMock.post(buildCacheEndpoint(Constants.PROJECTS), keyJson))
+    when(httpSessionMock.post(eq(buildCacheEndpoint(Constants.PROJECTS)), eq(keyJson), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.evict(Constants.PROJECTS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder.evict(Constants.PROJECTS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result())
         .isTrue();
   }
 
@@ -320,9 +363,10 @@
   public void testEvictAccountsOK() throws Exception {
     Account.Id key = Account.id(123);
     String keyJson = gson.toJson(key);
-    when(httpSessionMock.post(buildCacheEndpoint(Constants.ACCOUNTS), keyJson))
+    when(httpSessionMock.post(eq(buildCacheEndpoint(Constants.ACCOUNTS)), eq(keyJson), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.evict(Constants.ACCOUNTS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder.evict(Constants.ACCOUNTS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result())
         .isTrue();
   }
 
@@ -331,8 +375,10 @@
     AccountGroup.Id key = AccountGroup.id(123);
     String keyJson = gson.toJson(key);
     String endpoint = buildCacheEndpoint(Constants.GROUPS);
-    when(httpSessionMock.post(endpoint, keyJson)).thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.evict(Constants.GROUPS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    when(httpSessionMock.post(eq(endpoint), eq(keyJson), any()))
+        .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
+    assertThat(
+            forwarder.evict(Constants.GROUPS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result())
         .isTrue();
   }
 
@@ -340,10 +386,14 @@
   public void testEvictGroupsByIncludeOK() throws Exception {
     AccountGroup.UUID key = AccountGroup.uuid("90b3042d9094a37985f3f9281391dbbe9a5addad");
     String keyJson = gson.toJson(key);
-    when(httpSessionMock.post(buildCacheEndpoint(Constants.GROUPS_BYINCLUDE), keyJson))
+    when(httpSessionMock.post(
+            eq(buildCacheEndpoint(Constants.GROUPS_BYINCLUDE)), eq(keyJson), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
     assertThat(
-            forwarder.evict(Constants.GROUPS_BYINCLUDE, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+            forwarder
+                .evict(Constants.GROUPS_BYINCLUDE, key)
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
@@ -351,9 +401,13 @@
   public void testEvictGroupsMembersOK() throws Exception {
     AccountGroup.UUID key = AccountGroup.uuid("90b3042d9094a37985f3f9281391dbbe9a5addad");
     String keyJson = gson.toJson(key);
-    when(httpSessionMock.post(buildCacheEndpoint(Constants.GROUPS_MEMBERS), keyJson))
+    when(httpSessionMock.post(eq(buildCacheEndpoint(Constants.GROUPS_MEMBERS)), eq(keyJson), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.evict(Constants.GROUPS_MEMBERS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder
+                .evict(Constants.GROUPS_MEMBERS, key)
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
@@ -361,9 +415,10 @@
   public void testEvictCacheFailed() throws Exception {
     String key = PROJECT_NAME;
     String keyJson = gson.toJson(key);
-    when(httpSessionMock.post(buildCacheEndpoint(Constants.PROJECTS), keyJson))
+    when(httpSessionMock.post(eq(buildCacheEndpoint(Constants.PROJECTS)), eq(keyJson), any()))
         .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
-    assertThat(forwarder.evict(Constants.PROJECTS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder.evict(Constants.PROJECTS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result())
         .isFalse();
   }
 
@@ -371,10 +426,10 @@
   public void testEvictCacheThrowsException() throws Exception {
     String key = PROJECT_NAME;
     String keyJson = gson.toJson(key);
-    doThrow(new IOException())
-        .when(httpSessionMock)
-        .post(buildCacheEndpoint(Constants.PROJECTS), keyJson);
-    assertThat(forwarder.evict(Constants.PROJECTS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    when(httpSessionMock.post(eq(buildCacheEndpoint(Constants.PROJECTS)), eq(keyJson), any()))
+        .thenThrow(IOException.class);
+    assertThat(
+            forwarder.evict(Constants.PROJECTS, key).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result())
         .isFalse();
   }
 
@@ -385,56 +440,69 @@
   @Test
   public void testAddToProjectListOK() throws Exception {
     String projectName = PROJECT_TO_ADD;
-    when(httpSessionMock.post(buildProjectListCacheEndpoint(projectName), null))
+    when(httpSessionMock.post(eq(buildProjectListCacheEndpoint(projectName)), any(), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.addToProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder.addToProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result())
         .isTrue();
   }
 
   @Test
   public void testAddToProjectListFailed() throws Exception {
     String projectName = PROJECT_TO_ADD;
-    when(httpSessionMock.post(buildProjectListCacheEndpoint(projectName), null))
+    when(httpSessionMock.post(eq(buildProjectListCacheEndpoint(projectName)), any(), any()))
         .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
-    assertThat(forwarder.addToProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder.addToProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result())
         .isFalse();
   }
 
   @Test
   public void testAddToProjectListThrowsException() throws Exception {
     String projectName = PROJECT_TO_ADD;
-    doThrow(new IOException())
-        .when(httpSessionMock)
-        .post(buildProjectListCacheEndpoint(projectName), null);
-    assertThat(forwarder.addToProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    when(httpSessionMock.post(eq(buildProjectListCacheEndpoint(projectName)), any(), any()))
+        .thenThrow(IOException.class);
+    assertThat(
+            forwarder.addToProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS).result())
         .isFalse();
   }
 
   @Test
   public void testRemoveFromProjectListOK() throws Exception {
     String projectName = PROJECT_TO_DELETE;
-    when(httpSessionMock.delete(buildProjectListCacheEndpoint(projectName)))
+    when(httpSessionMock.delete(eq(buildProjectListCacheEndpoint(projectName)), any()))
         .thenReturn(new HttpResult(SUCCESSFUL, EMPTY_MSG));
-    assertThat(forwarder.removeFromProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder
+                .removeFromProjectList(projectName)
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
   @Test
   public void testRemoveToProjectListFailed() throws Exception {
     String projectName = PROJECT_TO_DELETE;
-    when(httpSessionMock.delete(buildProjectListCacheEndpoint(projectName)))
+    when(httpSessionMock.delete(eq(buildProjectListCacheEndpoint(projectName)), any()))
         .thenReturn(new HttpResult(FAILED, EMPTY_MSG));
-    assertThat(forwarder.removeFromProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    assertThat(
+            forwarder
+                .removeFromProjectList(projectName)
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testRemoveToProjectListThrowsException() throws Exception {
     String projectName = PROJECT_TO_DELETE;
-    doThrow(new IOException())
-        .when(httpSessionMock)
-        .delete((buildProjectListCacheEndpoint(projectName)));
-    assertThat(forwarder.removeFromProjectList(projectName).get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+    when(httpSessionMock.delete(eq(buildProjectListCacheEndpoint(projectName)), any()))
+        .thenThrow(IOException.class);
+    assertThat(
+            forwarder
+                .removeFromProjectList(projectName)
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
@@ -444,7 +512,7 @@
 
   @Test
   public void testRetryOnErrorThenSuccess() throws Exception {
-    when(httpSessionMock.post(anyString(), anyString()))
+    when(httpSessionMock.post(anyString(), anyString(), any()))
         .thenReturn(new HttpResult(false, ERROR))
         .thenReturn(new HttpResult(false, ERROR))
         .thenReturn(new HttpResult(true, SUCCESS));
@@ -452,13 +520,14 @@
     assertThat(
             forwarder
                 .evict(Constants.PROJECT_LIST, new Object())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
   @Test
   public void testRetryOnIoExceptionThenSuccess() throws Exception {
-    when(httpSessionMock.post(anyString(), anyString()))
+    when(httpSessionMock.post(anyString(), anyString(), any()))
         .thenThrow(new IOException())
         .thenThrow(new IOException())
         .thenReturn(new HttpResult(true, SUCCESS));
@@ -466,26 +535,28 @@
     assertThat(
             forwarder
                 .evict(Constants.PROJECT_LIST, new Object())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isTrue();
   }
 
   @Test
   public void testNoRetryAfterNonRecoverableException() throws Exception {
-    when(httpSessionMock.post(anyString(), anyString()))
+    when(httpSessionMock.post(anyString(), anyString(), any()))
         .thenThrow(new SSLException("Non Recoverable"))
         .thenReturn(new HttpResult(true, SUCCESS));
 
     assertThat(
             forwarder
                 .evict(Constants.PROJECT_LIST, new Object())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 
   @Test
   public void testFailureAfterMaxTries() throws Exception {
-    when(httpSessionMock.post(anyString(), anyString()))
+    when(httpSessionMock.post(anyString(), anyString(), any()))
         .thenReturn(new HttpResult(false, ERROR))
         .thenReturn(new HttpResult(false, ERROR))
         .thenReturn(new HttpResult(false, ERROR));
@@ -493,7 +564,8 @@
     assertThat(
             forwarder
                 .evict(Constants.PROJECT_LIST, new Object())
-                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS))
+                .get(TEST_TIMEOUT, TEST_TIMEOUT_UNITS)
+                .result())
         .isFalse();
   }
 }

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeCheckerImplTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeCheckerImplTest.java
index dfea1df..460d56b 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeCheckerImplTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/index/ChangeCheckerImplTest.java

@@ -24,7 +24,6 @@
 import com.google.gerrit.server.notedb.ChangeNotes;
 import com.google.gerrit.server.util.OneOffRequestContext;
 import java.io.IOException;
-import java.sql.Timestamp;
 import java.time.Instant;
 import java.util.Optional;
 import org.junit.Before;
@@ -45,7 +44,7 @@
   private final Instant testLastUpdatedOn = Instant.now();
   private final String changeId = "1";
   Optional<IndexEvent> event = Optional.empty();
-  private Optional<Long> computedChangeTs = Optional.empty();
+  private Optional<Instant> computedChangeTs = Optional.empty();
   private ChangeCheckerImpl changeChecker;
 
   @Before
@@ -61,8 +60,7 @@
 
   @Test
   public void testGetComputedChangeTs() {
-    long testTime = Timestamp.from(testLastUpdatedOn).getTime();
-    computedChangeTs = Optional.of(testTime / 1000);
+    computedChangeTs = Optional.of(testLastUpdatedOn);
     when(changeChecker.getChangeNotes()).thenReturn(Optional.of(testChangeNotes));
     when(testChangeNotes.getChange()).thenReturn(testChange);
     when(testChange.getLastUpdatedOn()).thenReturn(testLastUpdatedOn);

diff --git a/src/test/java/com/ericsson/gerrit/plugins/highavailability/index/IndexEventHandlerTest.java b/src/test/java/com/ericsson/gerrit/plugins/highavailability/index/IndexEventHandlerTest.java
index a8aa4a9..a986b90 100644
--- a/src/test/java/com/ericsson/gerrit/plugins/highavailability/index/IndexEventHandlerTest.java
+++ b/src/test/java/com/ericsson/gerrit/plugins/highavailability/index/IndexEventHandlerTest.java

@@ -24,7 +24,9 @@
 
 import com.ericsson.gerrit.plugins.highavailability.Configuration;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.Context;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.EventType;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder;
+import com.ericsson.gerrit.plugins.highavailability.forwarder.Forwarder.Result;
 import com.ericsson.gerrit.plugins.highavailability.forwarder.IndexEvent;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.AccountGroup;
@@ -75,12 +77,17 @@
     when(changeCheckerMock.newIndexEvent()).thenReturn(Optional.of(new IndexEvent()));
 
     when(forwarder.indexAccount(eq(ACCOUNT_ID), any()))
-        .thenReturn(CompletableFuture.completedFuture(true));
+        .thenReturn(
+            CompletableFuture.completedFuture(new Result(EventType.INDEX_ACCOUNT_UPDATE, true)));
     when(forwarder.deleteChangeFromIndex(eq(CHANGE_ID), any()))
-        .thenReturn(CompletableFuture.completedFuture(true));
-    when(forwarder.indexGroup(eq(UUID), any())).thenReturn(CompletableFuture.completedFuture(true));
+        .thenReturn(
+            CompletableFuture.completedFuture(new Result(EventType.INDEX_CHANGE_DELETION, true)));
+    when(forwarder.indexGroup(eq(UUID), any()))
+        .thenReturn(
+            CompletableFuture.completedFuture(new Result(EventType.INDEX_GROUP_UPDATE, true)));
     when(forwarder.indexChange(eq(PROJECT_NAME), eq(CHANGE_ID), any()))
-        .thenReturn(CompletableFuture.completedFuture(true));
+        .thenReturn(
+            CompletableFuture.completedFuture(new Result(EventType.INDEX_CHANGE_UPDATE, true)));
 
     setUpIndexEventHandler(currCtx);
   }