diff --git a/internal/k8s/vald/annotations.go b/internal/k8s/vald/annotations.go
index c138871074..24ef49e6ce 100644
--- a/internal/k8s/vald/annotations.go
+++ b/internal/k8s/vald/annotations.go
@@ -19,9 +19,9 @@ package vald
 import "time"
 
 const (
-	TimestampLayout                              = time.RFC3339Nano
+	TimeFormat                                   = time.RFC3339Nano
 	UncommittedAnnotationsKey                    = "vald.vdaas.org/uncommitted"
-	UnsavedProcessedVqAnnotationsKey             = "vald.vdaas.org/unsaved-processed-vq"
+	UnsavedProcessedVQAnnotationsKey             = "vald.vdaas.org/unsaved-processed-vq"
 	UnsavedCreateIndexExecutionNumAnnotationsKey = "vald.vdaas.org/unsaved-create-index-execution"
 	LastTimeSaveIndexTimestampAnnotationsKey     = "vald.vdaas.org/last-time-save-index-timestamp"
 	IndexCountAnnotationsKey                     = "vald.vdaas.org/index-count"
diff --git a/pkg/agent/core/ngt/service/ngt.go b/pkg/agent/core/ngt/service/ngt.go
index 0cd08f0419..f1e1a80902 100644
--- a/pkg/agent/core/ngt/service/ngt.go
+++ b/pkg/agent/core/ngt/service/ngt.go
@@ -2007,7 +2007,7 @@ func (n *ngt) unsavedNumberOfCreateIndexExecutionEntry() (k, v string) {
 }
 
 func (n *ngt) lastTimeSaveIndexTimestampEntry(timestamp time.Time) (k, v string) {
-	return lastTimeSaveIndexTimestampAnnotationsKey, timestamp.UTC().Format(vald.TimestampLayout)
+	return lastTimeSaveIndexTimestampAnnotationsKey, timestamp.UTC().Format(vald.TimeFormat)
 }
 
 func (n *ngt) indexCountEntry() (k, v string) {
diff --git a/pkg/agent/core/ngt/service/ngt_test.go b/pkg/agent/core/ngt/service/ngt_test.go
index 95cef9565d..3adcf18726 100644
--- a/pkg/agent/core/ngt/service/ngt_test.go
+++ b/pkg/agent/core/ngt/service/ngt_test.go
@@ -1301,7 +1301,7 @@ func TestExportIndexInfo(t *testing.T) {
 					unsavedProcessedVqAnnotationsKey:             "2",
 				}
 				expectedAfterSave := map[string]string{
-					lastTimeSaveIndexTimestampAnnotationsKey:     saveIndexTime.UTC().Format(kvald.TimestampLayout),
+					lastTimeSaveIndexTimestampAnnotationsKey:     saveIndexTime.UTC().Format(kvald.TimeFormat),
 					unsavedCreateIndexExecutionNumAnnotationsKey: "0",
 					unsavedProcessedVqAnnotationsKey:             "0",
 				}
diff --git a/pkg/index/job/readreplica/rotate/service/rotator.go b/pkg/index/job/readreplica/rotate/service/rotator.go
index 1cd0de4ebf..ec64ac39bc 100644
--- a/pkg/index/job/readreplica/rotate/service/rotator.go
+++ b/pkg/index/job/readreplica/rotate/service/rotator.go
@@ -306,7 +306,7 @@ func (s *subProcess) updateDeployment(ctx context.Context, newPVC string, deploy
 	if deployment.Annotations == nil {
 		deployment.Annotations = map[string]string{}
 	}
-	deployment.Annotations[vald.LastTimeSnapshotTimestampAnnotationsKey] = snapshotTime.UTC().Format(vald.TimestampLayout)
+	deployment.Annotations[vald.LastTimeSnapshotTimestampAnnotationsKey] = snapshotTime.UTC().Format(vald.TimeFormat)
 
 	for _, vol := range deployment.Spec.Template.Spec.Volumes {
 		if vol.Name == s.volumeName {
diff --git a/pkg/index/operator/service/operator.go b/pkg/index/operator/service/operator.go
index 3108bc58f2..28d58e88e6 100644
--- a/pkg/index/operator/service/operator.go
+++ b/pkg/index/operator/service/operator.go
@@ -169,7 +169,7 @@ func (o *operator) rotateIfNeeded(ctx context.Context, pod pod.Pod) error {
 		log.Info("the agent pod has not saved index yet. skipping...")
 		return nil
 	}
-	lastSavedTime, err := time.Parse(vald.TimestampLayout, t)
+	lastSavedTime, err := time.Parse(vald.TimeFormat, t)
 	if err != nil {
 		return fmt.Errorf("parsing last time saved time: %w", err)
 	}
@@ -193,7 +193,7 @@ func (o *operator) rotateIfNeeded(ctx context.Context, pod pod.Pod) error {
 	annotations := dep.GetAnnotations()
 	t, ok = annotations[vald.LastTimeSnapshotTimestampAnnotationsKey]
 	if ok {
-		lastSnapshotTime, err := time.Parse(vald.TimestampLayout, t)
+		lastSnapshotTime, err := time.Parse(vald.TimeFormat, t)
 		if err != nil {
 			return fmt.Errorf("parsing last snapshot time: %w", err)
 		}