diff --git a/app/vminsert/common/insert_ctx.go b/app/vminsert/common/insert_ctx.go
index 33397fade..6f01c845b 100644
--- a/app/vminsert/common/insert_ctx.go
+++ b/app/vminsert/common/insert_ctx.go
@@ -41,7 +41,6 @@ func (ctx *InsertCtx) Reset(rowsLen int) {
 	}
 	ctx.mrs = ctx.mrs[:0]
 	ctx.metricNamesBuf = ctx.metricNamesBuf[:0]
-
 	ctx.relabelCtx.Reset()
 }
 
@@ -54,23 +53,28 @@ func (ctx *InsertCtx) marshalMetricNameRaw(prefix []byte, labels []prompb.Label)
 }
 
 // WriteDataPoint writes (timestamp, value) with the given prefix and labels into ctx buffer.
-func (ctx *InsertCtx) WriteDataPoint(prefix []byte, labels []prompb.Label, timestamp int64, value float64) {
+func (ctx *InsertCtx) WriteDataPoint(prefix []byte, labels []prompb.Label, timestamp int64, value float64) error {
 	metricNameRaw := ctx.marshalMetricNameRaw(prefix, labels)
-	ctx.addRow(metricNameRaw, timestamp, value)
+	return ctx.addRow(metricNameRaw, timestamp, value)
 }
 
 // WriteDataPointExt writes (timestamp, value) with the given metricNameRaw and labels into ctx buffer.
 //
 // It returns metricNameRaw for the given labels if len(metricNameRaw) == 0.
-func (ctx *InsertCtx) WriteDataPointExt(metricNameRaw []byte, labels []prompb.Label, timestamp int64, value float64) []byte {
+func (ctx *InsertCtx) WriteDataPointExt(metricNameRaw []byte, labels []prompb.Label, timestamp int64, value float64) ([]byte, error) {
 	if len(metricNameRaw) == 0 {
 		metricNameRaw = ctx.marshalMetricNameRaw(nil, labels)
 	}
-	ctx.addRow(metricNameRaw, timestamp, value)
-	return metricNameRaw
+	err := ctx.addRow(metricNameRaw, timestamp, value)
+	return metricNameRaw, err
 }
 
-func (ctx *InsertCtx) addRow(metricNameRaw []byte, timestamp int64, value float64) {
+func (ctx *InsertCtx) addRow(metricNameRaw []byte, timestamp int64, value float64) error {
+	if len(ctx.metricNamesBuf) > 16*1024*1024 {
+		if err := ctx.FlushBufs(); err != nil {
+			return err
+		}
+	}
 	mrs := ctx.mrs
 	if cap(mrs) > len(mrs) {
 		mrs = mrs[:len(mrs)+1]
@@ -82,6 +86,7 @@ func (ctx *InsertCtx) addRow(metricNameRaw []byte, timestamp int64, value float6
 	mr.MetricNameRaw = metricNameRaw
 	mr.Timestamp = timestamp
 	mr.Value = value
+	return nil
 }
 
 // AddLabelBytes adds (name, value) label to ctx.Labels.
@@ -127,11 +132,13 @@ func (ctx *InsertCtx) ApplyRelabeling() {
 
 // FlushBufs flushes buffered rows to the underlying storage.
 func (ctx *InsertCtx) FlushBufs() error {
-	if err := vmstorage.AddRows(ctx.mrs); err != nil {
-		return &httpserver.ErrorWithStatusCode{
-			Err:        fmt.Errorf("cannot store metrics: %w", err),
-			StatusCode: http.StatusServiceUnavailable,
-		}
+	err := vmstorage.AddRows(ctx.mrs)
+	ctx.Reset(0)
+	if err == nil {
+		return nil
+	}
+	return &httpserver.ErrorWithStatusCode{
+		Err:        fmt.Errorf("cannot store metrics: %w", err),
+		StatusCode: http.StatusServiceUnavailable,
 	}
-	return nil
 }
diff --git a/app/vminsert/csvimport/request_handler.go b/app/vminsert/csvimport/request_handler.go
index e3034b28e..23590476d 100644
--- a/app/vminsert/csvimport/request_handler.go
+++ b/app/vminsert/csvimport/request_handler.go
@@ -45,7 +45,9 @@ func insertRows(rows []parser.Row) error {
 			// Skip metric without labels.
 			continue
 		}
-		ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value)
+		if err := ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value); err != nil {
+			return err
+		}
 	}
 	rowsInserted.Add(len(rows))
 	rowsPerInsert.Update(float64(len(rows)))
diff --git a/app/vminsert/graphite/request_handler.go b/app/vminsert/graphite/request_handler.go
index 5b3c0e4d3..84532485c 100644
--- a/app/vminsert/graphite/request_handler.go
+++ b/app/vminsert/graphite/request_handler.go
@@ -45,7 +45,9 @@ func insertRows(rows []parser.Row) error {
 			// Skip metric without labels.
 			continue
 		}
-		ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value)
+		if err := ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value); err != nil {
+			return err
+		}
 	}
 	rowsInserted.Add(len(rows))
 	rowsPerInsert.Update(float64(len(rows)))
diff --git a/app/vminsert/influx/request_handler.go b/app/vminsert/influx/request_handler.go
index b6128c7d7..196117f01 100644
--- a/app/vminsert/influx/request_handler.go
+++ b/app/vminsert/influx/request_handler.go
@@ -98,7 +98,9 @@ func insertRows(db string, rows []parser.Row) error {
 					// Skip metric without labels.
 					continue
 				}
-				ic.WriteDataPoint(nil, ic.Labels, r.Timestamp, f.Value)
+				if err := ic.WriteDataPoint(nil, ic.Labels, r.Timestamp, f.Value); err != nil {
+					return err
+				}
 			}
 		} else {
 			ctx.metricNameBuf = storage.MarshalMetricNameRaw(ctx.metricNameBuf[:0], ic.Labels)
@@ -115,7 +117,9 @@ func insertRows(db string, rows []parser.Row) error {
 					// Skip metric without labels.
 					continue
 				}
-				ic.WriteDataPoint(ctx.metricNameBuf, ic.Labels[len(ic.Labels)-1:], r.Timestamp, f.Value)
+				if err := ic.WriteDataPoint(ctx.metricNameBuf, ic.Labels[len(ic.Labels)-1:], r.Timestamp, f.Value); err != nil {
+					return err
+				}
 			}
 		}
 		rowsTotal += len(r.Fields)
diff --git a/app/vminsert/opentsdb/request_handler.go b/app/vminsert/opentsdb/request_handler.go
index ae0c52c3d..852708862 100644
--- a/app/vminsert/opentsdb/request_handler.go
+++ b/app/vminsert/opentsdb/request_handler.go
@@ -45,7 +45,9 @@ func insertRows(rows []parser.Row) error {
 			// Skip metric without labels.
 			continue
 		}
-		ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value)
+		if err := ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value); err != nil {
+			return err
+		}
 	}
 	rowsInserted.Add(len(rows))
 	rowsPerInsert.Update(float64(len(rows)))
diff --git a/app/vminsert/opentsdbhttp/request_handler.go b/app/vminsert/opentsdbhttp/request_handler.go
index c2c888bd1..927d083b2 100644
--- a/app/vminsert/opentsdbhttp/request_handler.go
+++ b/app/vminsert/opentsdbhttp/request_handler.go
@@ -51,7 +51,9 @@ func insertRows(rows []parser.Row) error {
 			// Skip metric without labels.
 			continue
 		}
-		ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value)
+		if err := ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value); err != nil {
+			return err
+		}
 	}
 	rowsInserted.Add(len(rows))
 	rowsPerInsert.Update(float64(len(rows)))
diff --git a/app/vminsert/prometheusimport/request_handler.go b/app/vminsert/prometheusimport/request_handler.go
index e76feb87d..13e779fca 100644
--- a/app/vminsert/prometheusimport/request_handler.go
+++ b/app/vminsert/prometheusimport/request_handler.go
@@ -44,7 +44,9 @@ func insertRows(rows []parser.Row) error {
 			// Skip metric without labels.
 			continue
 		}
-		ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value)
+		if err := ctx.WriteDataPoint(nil, ctx.Labels, r.Timestamp, r.Value); err != nil {
+			return err
+		}
 	}
 	rowsInserted.Add(len(rows))
 	rowsPerInsert.Update(float64(len(rows)))
diff --git a/app/vminsert/prompush/push.go b/app/vminsert/prompush/push.go
index 15790be1e..8333c8974 100644
--- a/app/vminsert/prompush/push.go
+++ b/app/vminsert/prompush/push.go
@@ -53,9 +53,14 @@ func push(ctx *common.InsertCtx, tss []prompbmarshal.TimeSeries) {
 			continue
 		}
 		var metricNameRaw []byte
+		var err error
 		for i := range ts.Samples {
 			r := &ts.Samples[i]
-			metricNameRaw = ctx.WriteDataPointExt(metricNameRaw, ctx.Labels, r.Timestamp, r.Value)
+			metricNameRaw, err = ctx.WriteDataPointExt(metricNameRaw, ctx.Labels, r.Timestamp, r.Value)
+			if err != nil {
+				logger.Errorf("cannot write promscape data to storage: %s", err)
+				return
+			}
 		}
 		rowsTotal += len(ts.Samples)
 	}
diff --git a/app/vminsert/promremotewrite/request_handler.go b/app/vminsert/promremotewrite/request_handler.go
index 684038401..27a7ffb6e 100644
--- a/app/vminsert/promremotewrite/request_handler.go
+++ b/app/vminsert/promremotewrite/request_handler.go
@@ -49,9 +49,13 @@ func insertRows(timeseries []prompb.TimeSeries) error {
 			continue
 		}
 		var metricNameRaw []byte
+		var err error
 		for i := range ts.Samples {
 			r := &ts.Samples[i]
-			metricNameRaw = ctx.WriteDataPointExt(metricNameRaw, ctx.Labels, r.Timestamp, r.Value)
+			metricNameRaw, err = ctx.WriteDataPointExt(metricNameRaw, ctx.Labels, r.Timestamp, r.Value)
+			if err != nil {
+				return err
+			}
 		}
 		rowsTotal += len(ts.Samples)
 	}
diff --git a/app/vminsert/vmimport/request_handler.go b/app/vminsert/vmimport/request_handler.go
index 896c47e66..c015cede2 100644
--- a/app/vminsert/vmimport/request_handler.go
+++ b/app/vminsert/vmimport/request_handler.go
@@ -59,7 +59,9 @@ func insertRows(rows []parser.Row) error {
 		_ = timestamps[len(values)-1]
 		for j, value := range values {
 			timestamp := timestamps[j]
-			ic.WriteDataPoint(ctx.metricNameBuf, nil, timestamp, value)
+			if err := ic.WriteDataPoint(ctx.metricNameBuf, nil, timestamp, value); err != nil {
+				return err
+			}
 		}
 		rowsTotal += len(values)
 	}