diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index b94a8a8560..86c1108a4f 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -15,6 +15,7 @@ The following tip changes can be tested by building VictoriaMetrics components f
 
 ## tip
 
+* BUGFIX: prevent from excess CPU usage when the storage enters [read-only mode](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#readonly-mode).
 
 ## [v1.80.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.80.0)
 
diff --git a/lib/storage/partition.go b/lib/storage/partition.go
index 969211c83e..7946eeeebc 100644
--- a/lib/storage/partition.go
+++ b/lib/storage/partition.go
@@ -569,7 +569,7 @@ func (pt *partition) addRowsPart(rows []rawRow) {
 		atomic.AddUint64(&pt.smallAssistedMerges, 1)
 		return
 	}
-	if errors.Is(err, errNothingToMerge) || errors.Is(err, errForciblyStopped) {
+	if errors.Is(err, errNothingToMerge) || errors.Is(err, errForciblyStopped) || errors.Is(err, errReadOnlyMode) {
 		return
 	}
 	logger.Panicf("FATAL: cannot merge small parts: %s", err)
@@ -956,7 +956,7 @@ func (pt *partition) partsMerger(mergerFunc func(isFinal bool) error) error {
 			// The merger has been stopped.
 			return nil
 		}
-		if !errors.Is(err, errNothingToMerge) {
+		if !errors.Is(err, errNothingToMerge) && !errors.Is(err, errReadOnlyMode) {
 			return err
 		}
 		if finalMergeDelaySeconds > 0 && fasttime.UnixTimestamp()-lastMergeTime > finalMergeDelaySeconds {
@@ -1012,11 +1012,13 @@ func (pt *partition) canBackgroundMerge() bool {
 	return atomic.LoadUint32(pt.isReadOnly) == 0
 }
 
+var errReadOnlyMode = fmt.Errorf("storage is in readonly mode")
+
 func (pt *partition) mergeBigParts(isFinal bool) error {
 	if !pt.canBackgroundMerge() {
 		// Do not perform merge in read-only mode, since this may result in disk space shortage.
 		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2603
-		return nil
+		return errReadOnlyMode
 	}
 	maxOutBytes := getMaxOutBytes(pt.bigPartsPath, bigMergeWorkersCount)
 
@@ -1032,7 +1034,7 @@ func (pt *partition) mergeSmallParts(isFinal bool) error {
 	if !pt.canBackgroundMerge() {
 		// Do not perform merge in read-only mode, since this may result in disk space shortage.
 		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2603
-		return nil
+		return errReadOnlyMode
 	}
 	// Try merging small parts to a big part at first.
 	maxBigPartOutBytes := getMaxOutBytes(pt.bigPartsPath, bigMergeWorkersCount)