Fix replication lag histogram metric collision

Author: zawadzkidiana

common/metrics/defs.go

@@ -2727,6 +2727,7 @@ const (
 	ReplicationTasksFailed
 	ReplicationTasksLag
 	ExponentialReplicationTasksLag
+	ExponentialReplicationTasksLagCounts
 	ReplicationTasksLagRaw
 	ExponentialReplicationTasksLagRaw
 	ReplicationTasksDelay
@@ -3547,7 +3548,8 @@ var MetricDefs = map[ServiceIdx]map[MetricIdx]metricDefinition{
 		ReplicationTasksApplied:                                      {metricName: "replication_tasks_applied", metricType: Counter},
 		ReplicationTasksFailed:                                       {metricName: "replication_tasks_failed", metricType: Counter},
 		ReplicationTasksLag:                                          {metricName: "replication_tasks_lag", metricType: Timer},
-		ExponentialReplicationTasksLag:                               {metricName: "replication_tasks_lag_counts", metricType: Histogram, intExponentialBuckets: Mid1To16k},
+		ExponentialReplicationTasksLag:                               {metricName: "replication_tasks_lag_ns", metricType: Histogram, exponentialBuckets: Mid1ms24h},
+		ExponentialReplicationTasksLagCounts:                         {metricName: "replication_tasks_lag_counts", metricType: Histogram, intExponentialBuckets: Mid1To16k},
 		ReplicationTasksLagRaw:                                       {metricName: "replication_tasks_lag_raw", metricType: Timer},
 		ExponentialReplicationTasksLagRaw:                            {metricName: "replication_tasks_lag_raw_counts", metricType: Histogram, intExponentialBuckets: Mid1To16k},
 		ReplicationTasksDelay:                                        {metricName: "replication_tasks_delay", metricType: Histogram, buckets: ReplicationTaskDelayBucket},

service/history/replication/task_ack_manager.go

@@ -205,7 +205,7 @@ func (t *TaskAckManager) getTasks(ctx context.Context, pollingCluster string, la
 
 	lag := maxReadLevel - msgs.LastRetrievedMessageID
 	t.scope.RecordTimer(metrics.ReplicationTasksLag, time.Duration(lag))
-	t.scope.IntExponentialHistogram(metrics.ExponentialReplicationTasksLag, clampInt64ToInt(lag))
+	t.scope.IntExponentialHistogram(metrics.ExponentialReplicationTasksLagCounts, clampInt64ToInt(lag))
 
 	t.scope.RecordTimer(metrics.ReplicationTasksReturned, time.Duration(len(msgs.ReplicationTasks)))
 	t.scope.IntExponentialHistogram(metrics.ExponentialReplicationTasksReturned, len(msgs.ReplicationTasks))