On Fri, Nov 11, 2016 at 12:28 AM, Stephen Frost <sfr...@snowman.net> wrote:
> * Michael Paquier (michael.paqu...@gmail.com) wrote:
>> Thanks for the review! Waiting for a couple of days more is fine for
>> me. This won't change much. Attached is v15 with the fixes you
>> mentioned.
>
> I figured I'd go ahead and start looking into this (and it's pretty easy
> for me to discuss it with David, given he works in the same office ;).

Thanks!

> A couple initial comments:
>
>> diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
>> index adab2f8..38c2385 100644
>> --- a/doc/src/sgml/config.sgml
>> +++ b/doc/src/sgml/config.sgml
>> @@ -2826,12 +2826,9 @@ include_dir 'conf.d'
>>          parameter is greater than zero, the server will switch to a new
>>          segment file whenever this many seconds have elapsed since the last
>>          segment file switch, and there has been any database activity,
>> -        including a single checkpoint.  (Increasing
>> -        <varname>checkpoint_timeout</> will reduce unnecessary
>> -        checkpoints on an idle system.)
>> -        Note that archived files that are closed early
>> -        due to a forced switch are still the same length as completely full
>> -        files.  Therefore, it is unwise to use a very short
>> +        including a single checkpoint.  Note that archived files that are
>> +        closed early due to a forced switch are still the same length as
>> +        completely full files.  Therefore, it is unwise to use a very short
>>          <varname>archive_timeout</> &mdash; it will bloat your archive
>>          storage.  <varname>archive_timeout</> settings of a minute or so are
>>          usually reasonable.  You should consider using streaming 
>> replication,
>
> We should probably include in here that we may skip a checkpoint if no
> activity has happened, meaning that this is a safe setting to set for
> environments which are idle for long periods.

OK, here is the interesting bit I just updated (I cut the diff a bit
as the rest is just reformatting):
         parameter is greater than zero, the server will switch to a new
         segment file whenever this many seconds have elapsed since the last
         segment file switch, and there has been any database activity,
-        including a single checkpoint.  (Increasing
-        <varname>checkpoint_timeout</> will reduce unnecessary
-        checkpoints on an idle system.)
[...]
+        including a single checkpoint.  Checkpoints can however be skipped
+        if there is no database activity, making this parameter a safe
+        setting for environments which are idle for a long period of time.

> (I'm thinking embedded systems here).

(Those are most of my users :{) ).

On Fri, Nov 11, 2016 at 3:23 AM, David Steele <da...@pgmasters.net> wrote:
> On 11/10/16 1:03 PM, Stephen Frost wrote:
>> Agreed. You certainly may wish to log checkpoints, even on an embedded
>> or low I/o system, but logging that nothing is happening doesn't seem
>> useful except perhaps for debugging.
>
> Sure, DEBUG1 or DEBUG2 makes sense.

OK. LOG was useful to avoid noise when debugging the thing, but DEBUG1
is fine for me as well in the final version.
-- 
Michael
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index adab2f8..d2a8ec2 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -2826,17 +2826,16 @@ include_dir 'conf.d'
         parameter is greater than zero, the server will switch to a new
         segment file whenever this many seconds have elapsed since the last
         segment file switch, and there has been any database activity,
-        including a single checkpoint.  (Increasing
-        <varname>checkpoint_timeout</> will reduce unnecessary
-        checkpoints on an idle system.)
-        Note that archived files that are closed early
-        due to a forced switch are still the same length as completely full
-        files.  Therefore, it is unwise to use a very short
-        <varname>archive_timeout</> &mdash; it will bloat your archive
-        storage.  <varname>archive_timeout</> settings of a minute or so are
-        usually reasonable.  You should consider using streaming replication,
-        instead of archiving, if you want data to be copied off the master
-        server more quickly than that.
+        including a single checkpoint.  Checkpoints can however be skipped
+        if there is no database activity, making this parameter a safe
+        setting for environments which are idle for a long period of time.
+        Note that archived files that are closed early due to a forced switch
+        are still the same length as completely full files.  Therefore, it is
+        unwise to use a very short <varname>archive_timeout</> &mdash; it will
+        bloat your archive storage.  <varname>archive_timeout</> settings of
+        a minute or so are usually reasonable.  You should consider using
+        streaming replication, instead of archiving, if you want data to
+        be copied off the master server more quickly than that.
         This parameter can only be set in the
         <filename>postgresql.conf</> file or on the server command line.
        </para>
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index b019bc1..ac40731 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -2507,7 +2507,7 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 							heaptup->t_len - SizeofHeapTupleHeader);
 
 		/* filtering by origin on a row level is much more efficient */
-		XLogIncludeOrigin();
+		XLogSetFlags(XLOG_INCLUDE_ORIGIN);
 
 		recptr = XLogInsert(RM_HEAP_ID, info);
 
@@ -2846,7 +2846,7 @@ heap_multi_insert(Relation relation, HeapTuple *tuples, int ntuples,
 			XLogRegisterBufData(0, tupledata, totaldatalen);
 
 			/* filtering by origin on a row level is much more efficient */
-			XLogIncludeOrigin();
+			XLogSetFlags(XLOG_INCLUDE_ORIGIN);
 
 			recptr = XLogInsert(RM_HEAP2_ID, info);
 
@@ -3308,7 +3308,7 @@ l1:
 		}
 
 		/* filtering by origin on a row level is much more efficient */
-		XLogIncludeOrigin();
+		XLogSetFlags(XLOG_INCLUDE_ORIGIN);
 
 		recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_DELETE);
 
@@ -6035,7 +6035,7 @@ heap_finish_speculative(Relation relation, HeapTuple tuple)
 		XLogBeginInsert();
 
 		/* We want the same filtering on this as on a plain insert */
-		XLogIncludeOrigin();
+		XLogSetFlags(XLOG_INCLUDE_ORIGIN);
 
 		XLogRegisterData((char *) &xlrec, SizeOfHeapConfirm);
 		XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
@@ -7703,7 +7703,7 @@ log_heap_update(Relation reln, Buffer oldbuf,
 	}
 
 	/* filtering by origin on a row level is much more efficient */
-	XLogIncludeOrigin();
+	XLogSetFlags(XLOG_INCLUDE_ORIGIN);
 
 	recptr = XLogInsert(RM_HEAP_ID, info);
 
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index e11b229..9130816 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -5232,7 +5232,7 @@ XactLogCommitRecord(TimestampTz commit_time,
 		XLogRegisterData((char *) (&xl_origin), sizeof(xl_xact_origin));
 
 	/* we allow filtering by xacts */
-	XLogIncludeOrigin();
+	XLogSetFlags(XLOG_INCLUDE_ORIGIN);
 
 	return XLogInsert(RM_XACT_ID, info);
 }
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 6cec027..a676307 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -442,11 +442,31 @@ typedef struct XLogwrtResult
  * the WAL record is just copied to the page and the lock is released. But
  * to avoid the deadlock-scenario explained above, the indicator is always
  * updated before sleeping while holding an insertion lock.
+ *
+ * The progressAt values indicate the insertion progress used to determine
+ * WAL insertion activity since a previous checkpoint, which is aimed at
+ * finding out if a checkpoint should be skipped or not or if standby
+ * activity should be logged. Progress position is basically updated
+ * for all types of records, for the time being only snapshot logging
+ * is out of this scope to properly skip their logging on idle systems.
+ * Tracking the WAL activity directly in WALInsertLock has the advantage
+ * to not rely on taking an exclusive lock on all the WAL insertion locks,
+ * hence reducing the impact of the activity lookup. This takes also
+ * advantage to avoid 8-byte torn reads on some platforms by using the
+ * fact that each insert lock is located on the same cache line.
+ *
+ * XXX: There is still room for more improvements here, particularly
+ * WAL operations related to unlogged relations (INIT_FORKNUM) should not
+ * update the progress LSN as those relations are reset during crash
+ * recovery so enforcing buffers of such relations to be flushed for
+ * example in the case of a load only on unlogged relations is a waste
+ * of disk write.
  */
 typedef struct
 {
 	LWLock		lock;
 	XLogRecPtr	insertingAt;
+	XLogRecPtr	progressAt;
 } WALInsertLock;
 
 /*
@@ -885,6 +905,9 @@ static void WALInsertLockUpdateInsertingAt(XLogRecPtr insertingAt);
  * which pages need a full-page image, and retry.  If fpw_lsn is invalid, the
  * record is always inserted.
  *
+ * 'flags' gives more in-depth control on the record being inserted. See
+ * XLogSetFlags() for more details.
+ *
  * The first XLogRecData in the chain must be for the record header, and its
  * data must be MAXALIGNed.  XLogInsertRecord fills in the xl_prev and
  * xl_crc fields in the header, the rest of the header must already be filled
@@ -897,7 +920,9 @@ static void WALInsertLockUpdateInsertingAt(XLogRecPtr insertingAt);
  * WAL rule "write the log before the data".)
  */
 XLogRecPtr
-XLogInsertRecord(XLogRecData *rdata, XLogRecPtr fpw_lsn)
+XLogInsertRecord(XLogRecData *rdata,
+				 XLogRecPtr fpw_lsn,
+				 uint8 flags)
 {
 	XLogCtlInsert *Insert = &XLogCtl->Insert;
 	pg_crc32c	rdata_crc;
@@ -997,6 +1022,24 @@ XLogInsertRecord(XLogRecData *rdata, XLogRecPtr fpw_lsn)
 		inserted = true;
 	}
 
+	/*
+	 * Update the LSN progress positions. At least one WAL insertion lock
+	 * is already taken appropriately before doing that, and it is simpler
+	 * to do that here when the WAL record data and type are at hand.
+	 * Progress is set at the start position of the tracked record that is
+	 * being added, making checkpoint progress tracking easier as the control
+	 * file already saves the start LSN position of the last checkpoint. If
+	 * an exclusive lock is taken for WAL insertion there is no need to
+	 * update all the progress fields, only the first one.
+	 */
+	if ((flags & XLOG_NO_PROGRESS) == 0)
+	{
+		if (holdingAllLocks)
+			WALInsertLocks[0].l.progressAt = StartPos;
+		else
+			WALInsertLocks[MyLockNo].l.progressAt = StartPos;
+	}
+
 	if (inserted)
 	{
 		/*
@@ -4720,6 +4763,7 @@ XLOGShmemInit(void)
 	{
 		LWLockInitialize(&WALInsertLocks[i].l.lock, LWTRANCHE_WAL_INSERT);
 		WALInsertLocks[i].l.insertingAt = InvalidXLogRecPtr;
+		WALInsertLocks[i].l.progressAt = InvalidXLogRecPtr;
 	}
 
 	/*
@@ -7999,6 +8043,55 @@ GetFlushRecPtr(void)
 }
 
 /*
+ * GetProgressRecPtr -- Returns the newest WAL activity position, or in
+ * other words any activity not referring to standby logging or segment
+ * switches. Finding the last activity position is done by scanning each
+ * WAL insertion lock by taking directly the light-weight lock associated
+ * to it.
+ */
+XLogRecPtr
+GetProgressRecPtr(void)
+{
+	XLogRecPtr	res = InvalidXLogRecPtr;
+	int			i;
+
+	/*
+	 * Look at the latest LSN position referring to the activity done by
+	 * WAL insertion. An exclusive lock is taken because currently the
+	 * locking logic for WAL insertion only expects such a level of locking.
+	 * Taking a lock is as well necessary to prevent potential torn reads
+	 * on some platforms.
+	 */
+	for (i = 0; i < NUM_XLOGINSERT_LOCKS; i++)
+	{
+		XLogRecPtr	progress_lsn;
+
+		LWLockAcquire(&WALInsertLocks[i].l.lock, LW_EXCLUSIVE);
+		progress_lsn = WALInsertLocks[i].l.progressAt;
+		LWLockRelease(&WALInsertLocks[i].l.lock);
+
+		if (res < progress_lsn)
+			res = progress_lsn;
+	}
+
+	return res;
+}
+
+/*
+ * GetLastCheckpointRecPtr -- Returns the last checkpoint insert position.
+ */
+XLogRecPtr
+GetLastCheckpointRecPtr(void)
+{
+	XLogRecPtr	ckpt_lsn;
+
+	LWLockAcquire(ControlFileLock, LW_SHARED);
+	ckpt_lsn = ControlFile->checkPoint;
+	LWLockRelease(ControlFileLock);
+	return ckpt_lsn;
+}
+
+/*
  * Get the time of the last xlog segment switch
  */
 pg_time_t
@@ -8258,7 +8351,7 @@ CreateCheckPoint(int flags)
 	uint32		freespace;
 	XLogRecPtr	PriorRedoPtr;
 	XLogRecPtr	curInsert;
-	XLogRecPtr	prevPtr;
+	XLogRecPtr	progress_lsn;
 	VirtualTransactionId *vxids;
 	int			nvxids;
 
@@ -8339,35 +8432,32 @@ CreateCheckPoint(int flags)
 		checkPoint.oldestActiveXid = InvalidTransactionId;
 
 	/*
+	 * Get progress before acquiring insert locks to shorten the locked
+	 * section waiting ahead.
+	 */
+	progress_lsn = GetProgressRecPtr();
+
+	/*
 	 * We must block concurrent insertions while examining insert state to
 	 * determine the checkpoint REDO pointer.
 	 */
 	WALInsertLockAcquireExclusive();
 	curInsert = XLogBytePosToRecPtr(Insert->CurrBytePos);
-	prevPtr = XLogBytePosToRecPtr(Insert->PrevBytePos);
 
 	/*
-	 * If this isn't a shutdown or forced checkpoint, and we have not inserted
-	 * any XLOG records since the start of the last checkpoint, skip the
-	 * checkpoint.  The idea here is to avoid inserting duplicate checkpoints
-	 * when the system is idle. That wastes log space, and more importantly it
-	 * exposes us to possible loss of both current and previous checkpoint
-	 * records if the machine crashes just as we're writing the update.
-	 * (Perhaps it'd make even more sense to checkpoint only when the previous
-	 * checkpoint record is in a different xlog page?)
-	 *
-	 * If the previous checkpoint crossed a WAL segment, however, we create
-	 * the checkpoint anyway, to have the latest checkpoint fully contained in
-	 * the new segment. This is for a little bit of extra robustness: it's
-	 * better if you don't need to keep two WAL segments around to recover the
-	 * checkpoint.
+	 * If this isn't a shutdown or forced checkpoint, and if there has been no
+	 * WAL activity, skip the checkpoint.  The idea here is to avoid inserting
+	 * duplicate checkpoints when the system is idle. That wastes log space,
+	 * and more importantly it exposes us to possible loss of both current and
+	 * previous checkpoint records if the machine crashes just as we're writing
+	 * the update.
 	 */
 	if ((flags & (CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_END_OF_RECOVERY |
 				  CHECKPOINT_FORCE)) == 0)
 	{
-		if (prevPtr == ControlFile->checkPointCopy.redo &&
-			prevPtr / XLOG_SEG_SIZE == curInsert / XLOG_SEG_SIZE)
+		if (progress_lsn == ControlFile->checkPoint)
 		{
+			ereport(DEBUG1, (errmsg("checkpoint skipped")));
 			WALInsertLockRelease();
 			LWLockRelease(CheckpointLock);
 			END_CRIT_SECTION();
@@ -9133,6 +9223,8 @@ RequestXLogSwitch(void)
 
 	/* XLOG SWITCH has no data */
 	XLogBeginInsert();
+
+	XLogSetFlags(XLOG_NO_PROGRESS);
 	RecPtr = XLogInsert(RM_XLOG_ID, XLOG_SWITCH);
 
 	return RecPtr;
diff --git a/src/backend/access/transam/xloginsert.c b/src/backend/access/transam/xloginsert.c
index 3cd273b..5b0590c 100644
--- a/src/backend/access/transam/xloginsert.c
+++ b/src/backend/access/transam/xloginsert.c
@@ -73,8 +73,8 @@ static XLogRecData *mainrdata_head;
 static XLogRecData *mainrdata_last = (XLogRecData *) &mainrdata_head;
 static uint32 mainrdata_len;	/* total # of bytes in chain */
 
-/* Should the in-progress insertion log the origin? */
-static bool include_origin = false;
+/* status flags of the in-progress insertion */
+static uint8 status_flags = 0;
 
 /*
  * These are used to hold the record header while constructing a record.
@@ -201,7 +201,7 @@ XLogResetInsertion(void)
 	max_registered_block_id = 0;
 	mainrdata_len = 0;
 	mainrdata_last = (XLogRecData *) &mainrdata_head;
-	include_origin = false;
+	status_flags = 0;
 	begininsert_called = false;
 }
 
@@ -384,13 +384,20 @@ XLogRegisterBufData(uint8 block_id, char *data, int len)
 }
 
 /*
- * Should this record include the replication origin if one is set up?
+ * Set insert status flags for the upcoming WAL record.
+ *
+ * The flags that can be used here are:
+ * - XLOG_INCLUDE_ORIGIN, to determine if the replication origin should be
+ *   included in the record.
+ * - XLOG_NO_PROGRESS, to not update the WAL progress trackers when inserting
+ *   the record.
  */
 void
-XLogIncludeOrigin(void)
+XLogSetFlags(uint8 flags)
 {
 	Assert(begininsert_called);
-	include_origin = true;
+
+	status_flags = flags;
 }
 
 /*
@@ -450,7 +457,7 @@ XLogInsert(RmgrId rmid, uint8 info)
 		rdt = XLogRecordAssemble(rmid, info, RedoRecPtr, doPageWrites,
 								 &fpw_lsn);
 
-		EndPos = XLogInsertRecord(rdt, fpw_lsn);
+		EndPos = XLogInsertRecord(rdt, fpw_lsn, status_flags);
 	} while (EndPos == InvalidXLogRecPtr);
 
 	XLogResetInsertion();
@@ -701,7 +708,8 @@ XLogRecordAssemble(RmgrId rmid, uint8 info,
 	}
 
 	/* followed by the record's origin, if any */
-	if (include_origin && replorigin_session_origin != InvalidRepOriginId)
+	if ((status_flags & XLOG_INCLUDE_ORIGIN) != 0 &&
+		replorigin_session_origin != InvalidRepOriginId)
 	{
 		*(scratch++) = XLR_BLOCK_ID_ORIGIN;
 		memcpy(scratch, &replorigin_session_origin, sizeof(replorigin_session_origin));
diff --git a/src/backend/postmaster/bgwriter.c b/src/backend/postmaster/bgwriter.c
index c3f3356..bb7740e 100644
--- a/src/backend/postmaster/bgwriter.c
+++ b/src/backend/postmaster/bgwriter.c
@@ -78,12 +78,12 @@ int			BgWriterDelay = 200;
 #define LOG_SNAPSHOT_INTERVAL_MS 15000
 
 /*
- * LSN and timestamp at which we last issued a LogStandbySnapshot(), to avoid
- * doing so too often or repeatedly if there has been no other write activity
- * in the system.
+ * Last progress LSN and timestamp at which we last logged a standby
+ * snapshot, to avoid doing so too often or repeatedly if there has been
+ * no other write activity in the system.
  */
 static TimestampTz last_snapshot_ts;
-static XLogRecPtr last_snapshot_lsn = InvalidXLogRecPtr;
+static XLogRecPtr last_progress_lsn = InvalidXLogRecPtr;
 
 /*
  * Flags set by interrupt handlers for later service in the main loop.
@@ -308,7 +308,7 @@ BackgroundWriterMain(void)
 		 * check whether there has been any WAL inserted since the last time
 		 * we've logged a running xacts.
 		 *
-		 * We do this logging in the bgwriter as its the only process that is
+		 * We do this logging in the bgwriter as it is the only process that is
 		 * run regularly and returns to its mainloop all the time. E.g.
 		 * Checkpointer, when active, is barely ever in its mainloop and thus
 		 * makes it hard to log regularly.
@@ -317,19 +317,23 @@ BackgroundWriterMain(void)
 		{
 			TimestampTz timeout = 0;
 			TimestampTz now = GetCurrentTimestamp();
+			XLogRecPtr	current_progress_lsn = GetProgressRecPtr();
 
 			timeout = TimestampTzPlusMilliseconds(last_snapshot_ts,
 												  LOG_SNAPSHOT_INTERVAL_MS);
 
 			/*
-			 * only log if enough time has passed and some xlog record has
-			 * been inserted.
+			 * Only log if enough time has passed, that some WAL activity
+			 * has happened since last checkpoint, and that some new WAL
+			 * records have been inserted since the last time we came here.
 			 */
 			if (now >= timeout &&
-				last_snapshot_lsn != GetXLogInsertRecPtr())
+				GetLastCheckpointRecPtr() < current_progress_lsn &&
+				last_progress_lsn < current_progress_lsn)
 			{
-				last_snapshot_lsn = LogStandbySnapshot();
+				(void) LogStandbySnapshot();
 				last_snapshot_ts = now;
+				last_progress_lsn = current_progress_lsn;
 			}
 		}
 
diff --git a/src/backend/postmaster/checkpointer.c b/src/backend/postmaster/checkpointer.c
index 397267c..7ecc00e 100644
--- a/src/backend/postmaster/checkpointer.c
+++ b/src/backend/postmaster/checkpointer.c
@@ -164,6 +164,7 @@ static double ckpt_cached_elapsed;
 
 static pg_time_t last_checkpoint_time;
 static pg_time_t last_xlog_switch_time;
+static XLogRecPtr last_xlog_switch_lsn = InvalidXLogRecPtr;
 
 /* Prototypes for private functions */
 
@@ -601,19 +602,36 @@ CheckArchiveTimeout(void)
 	/* Now we can do the real check */
 	if ((int) (now - last_xlog_switch_time) >= XLogArchiveTimeout)
 	{
-		XLogRecPtr	switchpoint;
-
-		/* OK, it's time to switch */
-		switchpoint = RequestXLogSwitch();
-
 		/*
-		 * If the returned pointer points exactly to a segment boundary,
-		 * assume nothing happened.
+		 * Switch segment only when WAL has done some progress since the
+		 * last time a segment has switched because of a timeout. Segment
+		 * switching because of other reasons, like manual triggering of
+		 * pg_switch_xlog() as well as this automatic switch, will not
+		 * cause any progress in WAL.  Note that RequestXLogSwitch() may
+		 * return the beginning of a segment, which is fine to prevent
+		 * any unnecessary switches to happen.
 		 */
-		if ((switchpoint % XLogSegSize) != 0)
-			ereport(DEBUG1,
-				(errmsg("transaction log switch forced (archive_timeout=%d)",
-						XLogArchiveTimeout)));
+		if (GetProgressRecPtr() > last_xlog_switch_lsn)
+		{
+			XLogRecPtr	switchpoint;
+
+			switchpoint = RequestXLogSwitch();
+
+			/*
+			 * If the returned pointer points exactly to a segment boundary,
+			 * assume nothing happened.
+			 */
+			if ((switchpoint % XLogSegSize) != 0)
+				ereport(DEBUG1,
+						(errmsg("transaction log switch forced (archive_timeout=%d)",
+								XLogArchiveTimeout)));
+
+			/*
+			 * Save the segment switch LSN. This may refer to the beginning of
+			 * the next new segment in case of consecutive switches.
+			 */
+			last_xlog_switch_lsn = switchpoint;
+		}
 
 		/*
 		 * Update state in any case, so we don't retry constantly when the
diff --git a/src/backend/replication/logical/message.c b/src/backend/replication/logical/message.c
index 8f9dc2f..c2d2bd8 100644
--- a/src/backend/replication/logical/message.c
+++ b/src/backend/replication/logical/message.c
@@ -73,7 +73,7 @@ LogLogicalMessage(const char *prefix, const char *message, size_t size,
 	XLogRegisterData((char *) message, size);
 
 	/* allow origin filtering */
-	XLogIncludeOrigin();
+	XLogSetFlags(XLOG_INCLUDE_ORIGIN);
 
 	return XLogInsert(RM_LOGICALMSG_ID, XLOG_LOGICAL_MESSAGE);
 }
diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c
index 875dcec..adc4e1d 100644
--- a/src/backend/storage/ipc/standby.c
+++ b/src/backend/storage/ipc/standby.c
@@ -964,7 +964,8 @@ LogStandbySnapshot(void)
  * The definitions of RunningTransactionsData and xl_xact_running_xacts
  * are similar. We keep them separate because xl_xact_running_xacts
  * is a contiguous chunk of memory and never exists fully until it is
- * assembled in WAL.
+ * assembled in WAL. Progress of WAL activity is not updated when
+ * this record is logged.
  */
 static XLogRecPtr
 LogCurrentRunningXacts(RunningTransactions CurrRunningXacts)
@@ -988,6 +989,8 @@ LogCurrentRunningXacts(RunningTransactions CurrRunningXacts)
 		XLogRegisterData((char *) CurrRunningXacts->xids,
 					   (xlrec.xcnt + xlrec.subxcnt) * sizeof(TransactionId));
 
+	XLogSetFlags(XLOG_NO_PROGRESS);
+
 	recptr = XLogInsert(RM_STANDBY_ID, XLOG_RUNNING_XACTS);
 
 	if (CurrRunningXacts->subxid_overflow)
@@ -1035,6 +1038,7 @@ LogAccessExclusiveLocks(int nlocks, xl_standby_lock *locks)
 	XLogBeginInsert();
 	XLogRegisterData((char *) &xlrec, offsetof(xl_standby_locks, locks));
 	XLogRegisterData((char *) locks, nlocks * sizeof(xl_standby_lock));
+	XLogSetFlags(XLOG_NO_PROGRESS);
 
 	(void) XLogInsert(RM_STANDBY_ID, XLOG_STANDBY_LOCK);
 }
diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index c9f332c..338c796 100644
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -184,6 +184,12 @@ extern bool XLOG_DEBUG;
 #define CHECKPOINT_CAUSE_XLOG	0x0040	/* XLOG consumption */
 #define CHECKPOINT_CAUSE_TIME	0x0080	/* Elapsed time */
 
+/*
+ * Flag bits for the record currently inserted.
+ */
+#define XLOG_INCLUDE_ORIGIN	0x01	/* include the replication origin */
+#define XLOG_NO_PROGRESS	0x02	/* do not update progress LSN */
+
 /* Checkpoint statistics */
 typedef struct CheckpointStatsData
 {
@@ -211,7 +217,9 @@ extern CheckpointStatsData CheckpointStats;
 
 struct XLogRecData;
 
-extern XLogRecPtr XLogInsertRecord(struct XLogRecData *rdata, XLogRecPtr fpw_lsn);
+extern XLogRecPtr XLogInsertRecord(struct XLogRecData *rdata,
+								   XLogRecPtr fpw_lsn,
+								   uint8 flags);
 extern void XLogFlush(XLogRecPtr RecPtr);
 extern bool XLogBackgroundFlush(void);
 extern bool XLogNeedsFlush(XLogRecPtr RecPtr);
@@ -262,6 +270,8 @@ extern void GetFullPageWriteInfo(XLogRecPtr *RedoRecPtr_p, bool *doPageWrites_p)
 extern XLogRecPtr GetRedoRecPtr(void);
 extern XLogRecPtr GetInsertRecPtr(void);
 extern XLogRecPtr GetFlushRecPtr(void);
+extern XLogRecPtr GetProgressRecPtr(void);
+extern XLogRecPtr GetLastCheckpointRecPtr(void);
 extern void GetNextXidAndEpoch(TransactionId *xid, uint32 *epoch);
 extern void RemovePromoteSignalFiles(void);
 
diff --git a/src/include/access/xloginsert.h b/src/include/access/xloginsert.h
index cc0177e..3f10919 100644
--- a/src/include/access/xloginsert.h
+++ b/src/include/access/xloginsert.h
@@ -40,7 +40,7 @@
 
 /* prototypes for public functions in xloginsert.c: */
 extern void XLogBeginInsert(void);
-extern void XLogIncludeOrigin(void);
+extern void XLogSetFlags(uint8 flags);
 extern XLogRecPtr XLogInsert(RmgrId rmid, uint8 info);
 extern void XLogEnsureRecordSpace(int nbuffers, int ndatas);
 extern void XLogRegisterData(char *data, int len);
-- 
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