Re: Patch for fail-back without fresh backup

On 2013-06-14 09:21:12 -0700, Jeff Davis wrote:
> On Fri, 2013-06-14 at 16:10 +0200, Andres Freund wrote:
> > Jeff Davis has a patch pending
> > (1365493015(dot)7580(dot)3240(dot)camel(at)sussancws0025) that passes the buffer_std
> > flag down to MarkBufferDirtyHint() for exactly that reason. I thought we
> > were on track committing that, but rereading the thread it doesn't look
> > that way.
> >
> > Jeff, care to update that patch?
>
> Rebased and attached. Changed so all callers use buffer_std=true except
> those in freespace.c and fsmpage.c.
>
> Simon, did you (or anyone else) have an objection to this patch? If not,
> I'll go ahead and commit it tomorrow morning.

I'd like to see a comment around the memcpys in XLogSaveBufferForHint()
that mentions that they are safe in a non std buffer due to
XLogCheckBuffer setting an appropriate hole/offset. Or make an explicit
change of the copy algorithm there.

Btw, if you touch that code, I'd vote for renaming XLOG_HINT to XLOG_FPI
or something like that. I find the former name confusing...

Greetings,

Andres Freund

--
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