Re: Checkpointer split has broken things dramatically (was Re: DELETE vs TRUNCATE explanation)

On Tue, Jul 17, 2012 at 06:56:50PM -0400, Tom Lane wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> > On Mon, Jul 16, 2012 at 3:18 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >> BTW, while we are on the subject: hasn't this split completely
> >> broken the statistics about backend-initiated writes?
>
> > Yes, it seems to have done just that.
>
> This implies that nobody has done pull-the-plug testing on either
> HEAD or 9.2 since the checkpointer split went in (2011-11-01),
> because even a modicum of such testing would surely have shown that
> we're failing to fsync a significant fraction of our write traffic.
>
> Furthermore, I would say that any performance testing done since
> then, if it wasn't looking at purely read-only scenarios, isn't
> worth the electrons it's written on. In particular, any performance
> gain that anybody might have attributed to the checkpointer splitup
> is very probably hogwash.
>
> This is not giving me a warm feeling about our testing practices.

Is there any part of this that the buildfarm, or some other automation
framework, might be able to handle?

Cheers,
David.
--
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