WAL receiver shouldn't try to send a reply when dying.

Per report from, and discussion with, Fujii Masao.

diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index 3277da8fc33029aeff1f5c775f0ea747775b7231..b1e5247f12af12fde8801d5fef060d509acfd6ff 100644 (file)
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -118,7 +118,7 @@ static void DisableWalRcvImmediateExit(void);
 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(void);
+static void XLogWalRcvFlush(bool dying);
 static void XLogWalRcvSendReply(void);
 
 /* Signal handlers */
@@ -319,7 +319,7 @@ WalReceiverMain(void)
                         * If we've written some records, flush them to disk and let the
                         * startup process know about them.
                         */
-                       XLogWalRcvFlush();
+                       XLogWalRcvFlush(false);
                }
                else
                {
@@ -342,7 +342,7 @@ WalRcvDie(int code, Datum arg)
        volatile WalRcvData *walrcv = WalRcv;
 
        /* Ensure that all WAL records received are flushed to disk */
-       XLogWalRcvFlush();
+       XLogWalRcvFlush(true);
 
        SpinLockAcquire(&walrcv->mutex);
        Assert(walrcv->walRcvState == WALRCV_RUNNING ||
@@ -461,7 +461,7 @@ XLogWalRcvWrite(char *buf, Size nbytes, XLogRecPtr recptr)
                         */
                        if (recvFile >= 0)
                        {
-                               XLogWalRcvFlush();
+                               XLogWalRcvFlush(false);
 
                                /*
                                 * XLOG segment files will be re-read by recovery in startup
@@ -531,9 +531,14 @@ XLogWalRcvWrite(char *buf, Size nbytes, XLogRecPtr recptr)
        }
 }
 
-/* Flush the log to disk */
+/*
+ * Flush the log to disk.
+ *
+ * If we're in the midst of dying, it's unwise to do anything that might throw
+ * an error, so we skip sending a reply in that case.
+ */
 static void
-XLogWalRcvFlush(void)
+XLogWalRcvFlush(bool dying)
 {
        if (XLByteLT(LogstreamResult.Flush, LogstreamResult.Write))
        {
@@ -565,7 +570,8 @@ XLogWalRcvFlush(void)
                }
 
                /* Also let the master know that we made some progress */
-               XLogWalRcvSendReply();
+               if (!dying)
+                       XLogWalRcvSendReply();
        }
 }