walreceiver_notify_archive_soon_v4.patch

diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index 9a2bc37fd7..8d7f52352d 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -125,6 +125,7 @@ static void WalRcvDie(int code, Datum arg);
 static void XLogWalRcvProcessMsg(unsigned char type, char *buf, Size len);
 static void XLogWalRcvWrite(char *buf, Size nbytes, XLogRecPtr recptr);
 static void XLogWalRcvFlush(bool dying);
+static void XLogWalRcvClose(XLogRecPtr recptr);
 static void XLogWalRcvSendReply(bool force, bool requestReply);
 static void XLogWalRcvSendHSFeedback(bool immed);
 static void ProcessWalSndrMessage(XLogRecPtr walEnd, TimestampTz sendTime);
@@ -883,42 +884,12 @@ XLogWalRcvWrite(char *buf, Size nbytes, XLogRecPtr recptr)
 	{
 		int			segbytes;
 
-		if (recvFile < 0 || !XLByteInSeg(recptr, recvSegNo, wal_segment_size))
+		/* Close the current segment if it's completed */
+		if (recvFile >= 0 && !XLByteInSeg(recptr, recvSegNo, wal_segment_size))
+			XLogWalRcvClose(recptr);
+
+		if (recvFile < 0)
 		{
-			/*
-			 * fsync() and close current file before we switch to next one. We
-			 * would otherwise have to reopen this file to fsync it later
-			 */
-			if (recvFile >= 0)
-			{
-				char		xlogfname[MAXFNAMELEN];
-
-				XLogWalRcvFlush(false);
-
-				XLogFileName(xlogfname, recvFileTLI, recvSegNo, wal_segment_size);
-
-				/*
-				 * XLOG segment files will be re-read by recovery in startup
-				 * process soon, so we don't advise the OS to release cache
-				 * pages associated with the file like XLogFileClose() does.
-				 */
-				if (close(recvFile) != 0)
-					ereport(PANIC,
-							(errcode_for_file_access(),
-							 errmsg("could not close log segment %s: %m",
-									xlogfname)));
-
-				/*
-				 * Create .done file forcibly to prevent the streamed segment
-				 * from being archived later.
-				 */
-				if (XLogArchiveMode != ARCHIVE_MODE_ALWAYS)
-					XLogArchiveForceDone(xlogfname);
-				else
-					XLogArchiveNotify(xlogfname);
-			}
-			recvFile = -1;
-
 			/* Create/use new log file */
 			XLByteToSeg(recptr, recvSegNo, wal_segment_size);
 			recvFile = XLogFileInit(recvSegNo);
@@ -967,6 +938,15 @@ XLogWalRcvWrite(char *buf, Size nbytes, XLogRecPtr recptr)
 
 	/* Update shared-memory status */
 	pg_atomic_write_u64(&WalRcv->writtenUpto, LogstreamResult.Write);
+
+	/*
+	 * Close the current segment if it's fully written up in the last cycle of
+	 * the loop, to create its archive notification file soon. Otherwise WAL
+	 * archiving of the segment will be delayed until any data in the next
+	 * segment is received and written.
+	 */
+	if (recvFile >= 0 && !XLByteInSeg(recptr, recvSegNo, wal_segment_size))
+		XLogWalRcvClose(recptr);
 }
 
 /*
@@ -1020,6 +1000,52 @@ XLogWalRcvFlush(bool dying)
 	}
 }
 
+/*
+ * Close the current segment.
+ *
+ * Flush the segment to disk before closing it. Otherwise we have to
+ * reopen and fsync it later.
+ *
+ * Create an archive notification file since the segment is known completed.
+ */
+static void
+XLogWalRcvClose(XLogRecPtr recptr)
+{
+	char		xlogfname[MAXFNAMELEN];
+
+	Assert(recvFile >= 0 && !XLByteInSeg(recptr, recvSegNo, wal_segment_size));
+
+	/*
+	 * fsync() and close current file before we switch to next one. We
+	 * would otherwise have to reopen this file to fsync it later
+	 */
+	XLogWalRcvFlush(false);
+
+	XLogFileName(xlogfname, recvFileTLI, recvSegNo, wal_segment_size);
+
+	/*
+	 * XLOG segment files will be re-read by recovery in startup process
+	 * soon, so we don't advise the OS to release cache pages associated
+	 * with the file like XLogFileClose() does.
+	 */
+	if (close(recvFile) != 0)
+		ereport(PANIC,
+				(errcode_for_file_access(),
+				 errmsg("could not close log segment %s: %m",
+						xlogfname)));
+
+	/*
+	 * Create .done file forcibly to prevent the streamed segment from
+	 * being archived later.
+	 */
+	if (XLogArchiveMode != ARCHIVE_MODE_ALWAYS)
+		XLogArchiveForceDone(xlogfname);
+	else
+		XLogArchiveNotify(xlogfname);
+
+	recvFile = -1;
+}
+
 /*
  * Send reply message to primary, indicating our current WAL locations, oldest
  * xmin and the current time.