diff --git a/common/metrics/metric_defs.go b/common/metrics/metric_defs.go
index cfbbe44687b..9a5c2f47cdc 100644
--- a/common/metrics/metric_defs.go
+++ b/common/metrics/metric_defs.go
@@ -1474,6 +1474,7 @@ var (
 	ShardLockLatency                               = NewTimerDef("shard_lock_latency")
 	NamespaceRegistryLockLatency                   = NewTimerDef("namespace_registry_lock_latency")
 	ClosedWorkflowBufferEventCount                 = NewCounterDef("closed_workflow_buffer_event_counter")
+	InorderBufferedEventsCounter                   = NewCounterDef("inordered_buffered_events")
 
 	// Matching
 	MatchingClientForwardedCounter            = NewCounterDef("forwarded")
diff --git a/service/history/workflow/history_builder.go b/service/history/workflow/history_builder.go
index 75ac1924b4e..d1798a0473f 100644
--- a/service/history/workflow/history_builder.go
+++ b/service/history/workflow/history_builder.go
@@ -39,6 +39,7 @@ import (
 	"go.temporal.io/server/api/historyservice/v1"
 	"go.temporal.io/server/common"
 	"go.temporal.io/server/common/clock"
+	"go.temporal.io/server/common/metrics"
 	"go.temporal.io/server/common/namespace"
 	"go.temporal.io/server/common/primitives/timestamp"
 )
@@ -90,6 +91,8 @@ type (
 
 		// scheduled to started event ID mapping
 		scheduledIDToStartedID map[int64]int64
+
+		metricsHandler metrics.Handler
 	}
 )
 
@@ -99,6 +102,7 @@ func NewMutableHistoryBuilder(
 	version int64,
 	nextEventID int64,
 	dbBufferBatch []*historypb.HistoryEvent,
+	metricsHandler metrics.Handler,
 ) *HistoryBuilder {
 	return &HistoryBuilder{
 		state:           HistoryBuilderStateMutable,
@@ -116,6 +120,8 @@ func NewMutableHistoryBuilder(
 		memLatestBatch:         nil,
 		memBufferBatch:         nil,
 		scheduledIDToStartedID: make(map[int64]int64),
+
+		metricsHandler: metricsHandler,
 	}
 }
 
@@ -139,6 +145,8 @@ func NewImmutableHistoryBuilder(
 		memLatestBatch:         history,
 		memBufferBatch:         nil,
 		scheduledIDToStartedID: nil,
+
+		metricsHandler: nil,
 	}
 }
 
@@ -1401,6 +1409,7 @@ func (b *HistoryBuilder) wireEventIDs(
 func (b *HistoryBuilder) reorderBuffer(
 	bufferEvents []*historypb.HistoryEvent,
 ) []*historypb.HistoryEvent {
+	b.emitInorderedBufferedEvents(bufferEvents)
 	reorderBuffer := make([]*historypb.HistoryEvent, 0, len(bufferEvents))
 	reorderEvents := make([]*historypb.HistoryEvent, 0, len(bufferEvents))
 	for _, event := range bufferEvents {
@@ -1423,6 +1432,47 @@ func (b *HistoryBuilder) reorderBuffer(
 	return append(reorderEvents, reorderBuffer...)
 }
 
+func (b *HistoryBuilder) emitInorderedBufferedEvents(bufferedEvents []*historypb.HistoryEvent) {
+	completedActivities := make(map[int64]struct{})
+	completedChildWorkflows := make(map[int64]struct{})
+	var inorderedEventsCount int64
+	for _, event := range bufferedEvents {
+		switch event.GetEventType() {
+		case enumspb.EVENT_TYPE_ACTIVITY_TASK_STARTED:
+			if _, seenCompleted := completedActivities[event.GetEventId()]; seenCompleted {
+				inorderedEventsCount++
+			}
+		case enumspb.EVENT_TYPE_ACTIVITY_TASK_COMPLETED:
+			completedActivities[event.GetActivityTaskCompletedEventAttributes().GetStartedEventId()] = struct{}{}
+		case enumspb.EVENT_TYPE_ACTIVITY_TASK_FAILED:
+			completedActivities[event.GetActivityTaskFailedEventAttributes().GetStartedEventId()] = struct{}{}
+		case enumspb.EVENT_TYPE_ACTIVITY_TASK_TIMED_OUT:
+			completedActivities[event.GetActivityTaskTimedOutEventAttributes().GetStartedEventId()] = struct{}{}
+		case enumspb.EVENT_TYPE_ACTIVITY_TASK_CANCELED:
+			completedActivities[event.GetActivityTaskCanceledEventAttributes().GetStartedEventId()] = struct{}{}
+
+		case enumspb.EVENT_TYPE_CHILD_WORKFLOW_EXECUTION_STARTED:
+			if _, seenCompleted := completedChildWorkflows[event.GetEventId()]; seenCompleted {
+				inorderedEventsCount++
+			}
+		case enumspb.EVENT_TYPE_CHILD_WORKFLOW_EXECUTION_COMPLETED:
+			completedChildWorkflows[event.GetChildWorkflowExecutionCompletedEventAttributes().GetStartedEventId()] = struct{}{}
+		case enumspb.EVENT_TYPE_CHILD_WORKFLOW_EXECUTION_FAILED:
+			completedChildWorkflows[event.GetChildWorkflowExecutionFailedEventAttributes().GetStartedEventId()] = struct{}{}
+		case enumspb.EVENT_TYPE_CHILD_WORKFLOW_EXECUTION_TIMED_OUT:
+			completedChildWorkflows[event.GetChildWorkflowExecutionTimedOutEventAttributes().GetStartedEventId()] = struct{}{}
+		case enumspb.EVENT_TYPE_CHILD_WORKFLOW_EXECUTION_CANCELED:
+			completedChildWorkflows[event.GetChildWorkflowExecutionCanceledEventAttributes().GetStartedEventId()] = struct{}{}
+		case enumspb.EVENT_TYPE_CHILD_WORKFLOW_EXECUTION_TERMINATED:
+			completedChildWorkflows[event.GetChildWorkflowExecutionTerminatedEventAttributes().GetStartedEventId()] = struct{}{}
+		}
+	}
+
+	if inorderedEventsCount > 0 && b.metricsHandler != nil {
+		b.metricsHandler.Counter(metrics.InorderBufferedEventsCounter.GetMetricName()).Record(inorderedEventsCount)
+	}
+}
+
 func (b *HistoryBuilder) HasActivityFinishEvent(
 	scheduledEventID int64,
 ) bool {
diff --git a/service/history/workflow/history_builder_test.go b/service/history/workflow/history_builder_test.go
index 82dd34c33ec..0145f18e159 100644
--- a/service/history/workflow/history_builder_test.go
+++ b/service/history/workflow/history_builder_test.go
@@ -45,6 +45,7 @@ import (
 	workflowspb "go.temporal.io/server/api/workflow/v1"
 	"go.temporal.io/server/common"
 	"go.temporal.io/server/common/clock"
+	"go.temporal.io/server/common/metrics"
 	"go.temporal.io/server/common/namespace"
 	"go.temporal.io/server/common/primitives/timestamp"
 	"go.temporal.io/server/service/history/tests"
@@ -154,6 +155,7 @@ func (s *historyBuilderSuite) SetupTest() {
 		s.version,
 		s.nextEventID,
 		nil,
+		metrics.NoopMetricsHandler,
 	)
 }
 
@@ -2088,6 +2090,7 @@ func (s *historyBuilderSuite) testWireEventIDs(
 		s.version,
 		s.nextEventID,
 		nil,
+		metrics.NoopMetricsHandler,
 	)
 	s.historyBuilder.dbBufferBatch = []*historypb.HistoryEvent{startEvent}
 	s.historyBuilder.memEventsBatches = nil
@@ -2134,6 +2137,7 @@ func (s *historyBuilderSuite) TestHasBufferEvent() {
 		s.version,
 		s.nextEventID,
 		nil,
+		metrics.NoopMetricsHandler,
 	)
 	historyBuilder.dbBufferBatch = nil
 	historyBuilder.memEventsBatches = nil
diff --git a/service/history/workflow/mutable_state_impl.go b/service/history/workflow/mutable_state_impl.go
index eaa3eb02aee..a817612a23d 100644
--- a/service/history/workflow/mutable_state_impl.go
+++ b/service/history/workflow/mutable_state_impl.go
@@ -265,6 +265,7 @@ func NewMutableState(
 		s.currentVersion,
 		common.FirstEventID,
 		s.bufferEventsInDB,
+		s.metricsHandler,
 	)
 	s.taskGenerator = taskGeneratorProvider.NewTaskGenerator(shard, s)
 	s.workflowTaskManager = newWorkflowTaskStateMachine(s)
@@ -326,6 +327,7 @@ func newMutableStateFromDB(
 		common.EmptyVersion,
 		dbRecord.NextEventId,
 		dbRecord.BufferedEvents,
+		mutableState.metricsHandler,
 	)
 
 	mutableState.currentVersion = common.EmptyVersion
@@ -527,6 +529,7 @@ func (ms *MutableStateImpl) UpdateCurrentVersion(
 		ms.currentVersion,
 		ms.nextEventIDInDB,
 		ms.bufferEventsInDB,
+		ms.metricsHandler,
 	)
 
 	return nil
@@ -4140,6 +4143,7 @@ func (ms *MutableStateImpl) cleanupTransaction(
 		ms.GetCurrentVersion(),
 		ms.nextEventIDInDB,
 		ms.bufferEventsInDB,
+		ms.metricsHandler,
 	)
 
 	ms.InsertTasks = make(map[tasks.Category][]tasks.Task)