master and slave snyc time

Code Source From: Self Code
Description:  【Optional】
Jira:  #【Optional】
市场项目编号（名称）：【Optional】

src/backend/replication/walreceiver.c

@@ -95,7 +95,8 @@ bool		hot_standby_feedback;
 static WalReceiverConn *wrconn = NULL;
 WalReceiverFunctionsType *WalReceiverFunctions = NULL;
 
-#define NAPTIME_PER_CYCLE 100	/* max sleep time between cycles (100ms) */
+//#define NAPTIME_PER_CYCLE 100	/* max sleep time between cycles (100ms) */
+#define NAPTIME_PER_CYCLE 10	/* max sleep time between cycles (10ms) */
 
 /*
  * These variables are used similarly to openLogFile/SegNo,
@@ -1124,6 +1125,11 @@ XLogWalRcvSendReply(bool force, bool requestReply)
 	writePtr = LogstreamResult.Write;
 	flushPtr = LogstreamResult.Flush;
 	applyPtr = GetXLogReplayRecPtr(NULL);
+#ifndef PG_NOREPLAY
+	if (push_standby == true) {
+		applyPtr = GetXLogPushToDisk();
+	}
+#endif
 
 	resetStringInfo(&reply_message);
 	pq_sendbyte(&reply_message, 'r');

src/backend/replication/walsender.c

@@ -1300,7 +1300,7 @@ WalSndWriteData(LogicalDecodingContext *ctx, XLogRecPtr lsn, TransactionId xid,
 			break;
 
 		sleeptime = WalSndComputeSleeptime(GetCurrentTimestamp());
-
+		sleeptime = 10; //10ms
 		/* Sleep until something happens or we time out */
 		WalSndWait(WL_SOCKET_WRITEABLE | WL_SOCKET_READABLE, sleeptime,
 				   WAIT_EVENT_WAL_SENDER_WRITE_DATA);
@@ -2374,7 +2374,7 @@ WalSndLoop(WalSndSendDataCallback send_data)
 			 * of reaching wal_sender_timeout before sending a keepalive.
 			 */
 			sleeptime = WalSndComputeSleeptime(GetCurrentTimestamp());
-
+			sleeptime = 10; //10ms
 			if (pq_is_send_pending())
 				wakeEvents |= WL_SOCKET_WRITEABLE;
 
@@ -3533,6 +3533,9 @@ WalSndKeepaliveIfNecessary(void)
 		/* Try to flush pending output to the client */
 		if (pq_flush_if_writable() != 0)
 			WalSndShutdown();
+	} else {
+		WalSndKeepalive(true);
+		pg_usleep(10000);
 	}
 }