On Thu, Nov 22, 2018 at 06:31:04PM +0800, Paul Guo wrote: > Yes, please see the attached patch.
Thanks, I have reviewed your patch, and could not resist to change SyncRepReleaseWaiters() on top of the rest with a comment to not be confused about the WAL sender states allowed to release waiters. The previous experience is proving that it seems unwise to rely on the order of the elements in WalSndState, so I have tweaked things so as the state is listed for all the code paths involved. Paul, what do you think? -- Michael
diff --git a/src/backend/replication/syncrep.c b/src/backend/replication/syncrep.c
index 9a13c50ce8..5b8a268fa1 100644
--- a/src/backend/replication/syncrep.c
+++ b/src/backend/replication/syncrep.c
@@ -425,10 +425,12 @@ SyncRepReleaseWaiters(void)
* If this WALSender is serving a standby that is not on the list of
* potential sync standbys then we have nothing to do. If we are still
* starting up, still running base backup or the current flush position is
- * still invalid, then leave quickly also.
+ * still invalid, then leave quickly also. Streaming or stopping WAL
+ * senders are allowed to release waiters.
*/
if (MyWalSnd->sync_standby_priority == 0 ||
- MyWalSnd->state < WALSNDSTATE_STREAMING ||
+ (MyWalSnd->state != WALSNDSTATE_STREAMING &&
+ MyWalSnd->state != WALSNDSTATE_STOPPING) ||
XLogRecPtrIsInvalid(MyWalSnd->flush))
{
announce_next_takeover = true;
@@ -730,8 +732,9 @@ SyncRepGetSyncStandbysQuorum(bool *am_sync)
if (pid == 0)
continue;
- /* Must be streaming */
- if (state != WALSNDSTATE_STREAMING)
+ /* Must be streaming or stopping */
+ if (state != WALSNDSTATE_STREAMING &&
+ state != WALSNDSTATE_STOPPING)
continue;
/* Must be synchronous */
@@ -809,8 +812,9 @@ SyncRepGetSyncStandbysPriority(bool *am_sync)
if (pid == 0)
continue;
- /* Must be streaming */
- if (state != WALSNDSTATE_STREAMING)
+ /* Must be streaming or stopping */
+ if (state != WALSNDSTATE_STREAMING &&
+ state != WALSNDSTATE_STOPPING)
continue;
/* Must be synchronous */
signature.asc
Description: PGP signature
