From: | Simon Riggs <simon(at)2ndQuadrant(dot)com> |
---|---|
To: | Fujii Masao <masao(dot)fujii(at)gmail(dot)com> |
Cc: | Robert Haas <robertmhaas(at)gmail(dot)com>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, pgsql-hackers(at)postgresql(dot)org |
Subject: | Re: Sync Rep v19 |
Date: | 2011-03-06 08:21:13 |
Message-ID: | 1299399673.1696.30.camel@ebony |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Sun, 2011-03-06 at 14:27 +0900, Fujii Masao wrote:
> On Sun, Mar 6, 2011 at 2:59 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> > On Sat, Mar 5, 2011 at 11:56 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> >>> 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
> >
> > I don't really see why sync rep should be responsible for solving this
> > problem, which is an issue in many other situations as well, only for
> > itself. In fact I think I'd prefer that it didn't, and that we wait
> > for a more general solution that will actually fix this problem for
> > real.
>
> I agree if such a general solution will be committed together with sync rep.
> Otherwise, because of sync rep, the backend can easily get stuck *infinitely*.
> When postmaster is not alive, all the existing walsenders exit immediately
> and no new walsender can appear. So there is no way to release the
> waiting backend. I think that some solutions for this issue which is likely to
> happen are required.
Completely agree.
--
Simon Riggs http://www.2ndQuadrant.com/books/
PostgreSQL Development, 24x7 Support, Training and Services
From | Date | Subject | |
---|---|---|---|
Next Message | Simon Riggs | 2011-03-06 08:26:18 | Re: Sync Rep v19 |
Previous Message | Fujii Masao | 2011-03-06 08:03:21 | Re: Replication server timeout patch |