Re: Uh, I change my mind about commit_delay + commit_siblings (sort of)

On 31 May 2012 13:16, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Thu, May 31, 2012 at 6:19 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> Frankly, I think this whole thing should be pushed to 9.3.  The
> commit_delay and commit_siblings knobs suck, but they've sucked for a
> long time, and it won't kill anybody to wait another release cycle to
> fix them.  We have plenty of more important things queued up for 9.3
> already, and I don't believe there's any compelling reason to think
> that this particular thing needs preferential treatment.

Why do you think that? Those knobs are now quite ineffective, though
we never even considered that when the group commit delay patch was
committed. The entire body of research and commentary that exists on
commit_delay has been invalidated for 9.2. If that isn't something
that needs to be addressed before release, I don't know what is. The
fact that the patch can sometimes double transaction throughput for an
absolutely trivial change, moving 2 lines of code, is also a good
reason to not bump this for another year.

--
Peter Geoghegan       http://www.2ndQuadrant.com/
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