Re: Sync Rep v19

On Sun, 2011-03-06 at 00:42 +0900, Fujii Masao wrote:
> On Sat, Mar 5, 2011 at 9:21 PM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> > I've added code to shmqueue.c to allow this.
> >
> > New version pushed.
>
> New comments;

None of the requested changes are in v21, as yet.

> It looks odd to report the sync_state of walsender in BACKUP
> state as ASYNC.

Cool.

> +SyncRepCleanupAtProcExit(int code, Datum arg)
> +{
> + if (WaitingForSyncRep && !SHMQueueIsDetached(&(MyProc->syncrep_links)))
> + {
> + LWLockAcquire(SyncRepLock, LW_EXCLUSIVE);
> + SHMQueueDelete(&(MyProc->syncrep_links));
> + LWLockRelease(SyncRepLock);
> + }
> +
> + if (MyProc != NULL)
> + DisownLatch(&MyProc->waitLatch);
>
> Can MyProc really be NULL here? If yes, "MyProc != NULL" should be
> checked before seeing MyProc->syncrep_links.

OK

> Even though postmaster dies, the waiting backend keeps waiting until
> the timeout expires. Instead, the backends should periodically check
> whether postmaster is alive, and then they should exit immediately
> if it's not alive, as well as other process does? If the timeout is
> disabled, such backends would get stuck infinitely.

Will wake them every 60 seconds

> Though I commented about the issue related to shutdown, that was
> pointless. So change of ProcessInterrupts is not required unless we
> find the need again. Sorry for the noise..

Yep, all gone now.

--
Simon Riggs http://www.2ndQuadrant.com/books/
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