Re: Hot Backup with rsync fails at pg_clog if under load

On Thu, Oct 27, 2011 at 3:13 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> However, the
> obvious next question is whether those other modules don't need to be
> changed also, and if not why not.

Good point.

StartupSubtrans() is also changed by this patch, since it will be
supplied with an earlier initialisation value.

StartupMultiXact() didn't need changing, I thought, but I will review further.

> Another issue is that if StartupCLog is left as a no-op, what will
> happen if someone mistakenly tries to access clog before the trim
> function is called?  It would be a good idea to make sure that such
> a thing results in an easily-identifiable failure.

The old StartupCLOG() didn't do anything that was essential to using
the clog, which is why its a no-op.

You can still use the clog, just with zero startup.

Maybe setting the current page should go in at startup, will think.

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