diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index d7973bc..a2b4aff 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -8343,8 +8343,12 @@ CreateCheckPoint(int flags)
 	if ((flags & (CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_END_OF_RECOVERY |
 				  CHECKPOINT_FORCE)) == 0)
 	{
+		elog(LOG, "Not a forced or shutdown checkpoint: progress_lsn %X/%X, ckpt %X/%X",
+			 (uint32) (progress_lsn >> 32), (uint32) progress_lsn,
+			 (uint32) (ControlFile->checkPoint >> 32), (uint32) ControlFile->checkPoint);
 		if (progress_lsn == ControlFile->checkPoint)
 		{
+			elog(LOG, "Checkpoint is skipped");
 			WALInsertLockRelease();
 			LWLockRelease(CheckpointLock);
 			END_CRIT_SECTION();
@@ -8511,7 +8515,11 @@ CreateCheckPoint(int flags)
 	 * recovery we don't need to write running xact data.
 	 */
 	if (!shutdown && XLogStandbyInfoActive())
-		LogStandbySnapshot();
+	{
+		XLogRecPtr lsn = LogStandbySnapshot();
+		elog(LOG, "snapshot taken by checkpoint %X/%X",
+			 (uint32) (lsn >> 32), (uint32) lsn);
+	}

 	START_CRIT_SECTION();

diff --git a/src/backend/postmaster/bgwriter.c b/src/backend/postmaster/bgwriter.c
index 79cfd7b..082e589 100644
--- a/src/backend/postmaster/bgwriter.c
+++ b/src/backend/postmaster/bgwriter.c
@@ -333,7 +333,9 @@ BackgroundWriterMain(void)
 				GetLastCheckpointRecPtr() < current_progress_lsn &&
 				last_progress_lsn < current_progress_lsn)
 			{
-				(void) LogStandbySnapshot();
+				XLogRecPtr lsn = LogStandbySnapshot();
+				elog(LOG, "snapshot taken by bgwriter %X/%X",
+					 (uint32) (lsn >> 32), (uint32) lsn);
 				last_snapshot_ts = now;
 				last_progress_lsn = current_progress_lsn;
 			}