diff --git a/br/pkg/lightning/common/ingest_data.go b/br/pkg/lightning/common/ingest_data.go
index e49949395b551..090118d1249e5 100644
--- a/br/pkg/lightning/common/ingest_data.go
+++ b/br/pkg/lightning/common/ingest_data.go
@@ -35,9 +35,9 @@ type IngestData interface {
 	// iterator is closed or ForwardIter.ReleaseBuf is called.
 	NewIter(ctx context.Context, lowerBound, upperBound []byte, bufPool *membuf.Pool) ForwardIter
 	// GetStartTS return the startTS when ingest. This TS should keep unchanged
-	// during retries of ingest. For local engine, it's set when engine is opened to
-	// avoid change too much code. For external engine, it's set when engine is
-	// closed.
+	// during retries of ingest. For local engine, it's set when engine is
+	// opened/reset to avoid change too much code. For external engine, it's set when
+	// engine is closed.
 	GetStartTS() uint64
 	// IncRef should be called every time when IngestData is referred by regionJob.
 	// Multiple regionJob can share one IngestData. Same amount of DecRef should be