diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index 0440f4a1d4..8f5e90be2a 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -2227,7 +2227,12 @@ pgstat_twophase_postcommit(TransactionId xid, uint16 info,
 	pgstat_info->t_counts.t_tuples_updated += rec->tuples_updated;
 	pgstat_info->t_counts.t_tuples_deleted += rec->tuples_deleted;
 	pgstat_info->t_counts.t_truncated = rec->t_truncated;
-
+	if (rec->t_truncated)
+	{
+		/* forget live/dead stats seen by backend thus far */
+		pgstat_info->t_counts.t_delta_live_tuples = 0;
+		pgstat_info->t_counts.t_delta_dead_tuples = 0;
+	}
 	pgstat_info->t_counts.t_delta_live_tuples +=
 		rec->tuples_inserted - rec->tuples_deleted;
 	pgstat_info->t_counts.t_delta_dead_tuples +=