relaxing sync commit if no WAL written (was Re: unlogged tables)

On Wed, Dec 15, 2010 at 2:20 AM, Heikki Linnakangas
<heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
> Looks ok. I'd suggest rewording this comment though:
>
> [ the comment in question ]
>
> It's a bit hard to follow, as it first lists exceptions on when we must
> flush XLOG immediately, and then lists conditions on when we can skip it.

See if the attached looks better to you. I mostly adopted your
proposal, with a bit of additional wordsmithing, and I also added a
parenthetical comment about why we don't skip writing the commit
record altogether in this case, since that's come up twice now.

I've removed the references to unlogged tables for now, as I'm
thinking it makes sense to commit this part first.

--
Robert Haas
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