Before exiting walreceiver, fsync() all the WAL received.

Otherwise WAL recovery will replay the un-flushed WAL after walreceiver has
exited, which can lead to a non-recoverable standby if the system crashes hard
at that point.

diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index d257caf..7005307 100644 (file)
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -324,6 +324,9 @@ WalRcvDie(int code, Datum arg)
        /* use volatile pointer to prevent code rearrangement */
        volatile WalRcvData *walrcv = WalRcv;
 
+       /* Ensure that all WAL records received are flushed to disk */
+       XLogWalRcvFlush();
+
        SpinLockAcquire(&walrcv->mutex);
        Assert(walrcv->walRcvState == WALRCV_RUNNING ||
                   walrcv->walRcvState == WALRCV_STOPPING);