Re: Ubuntu 12.04 / 3.2 Kernel Bad for PostgreSQL Performance

On Wed, Dec 5, 2012 at 10:28 AM, Shaun Thomas <sthomas(at)optionshouse(dot)com> wrote:
> Hey guys,
>
> This isn't a question, but a kind of summary over a ton of investigation
> I've been doing since a recent "upgrade". Anyone else out there with
> "big iron" might want to confirm this, but it seems pretty reproducible.
> This seems to affect the latest 3.2 mainline and by extension, any
> platform using it. My tests are restricted to Ubuntu 12.04, but it may
> apply elsewhere.
>
> Comparing the latest official 3.2 kernel to the latest official 3.4
> kernel (both Ubuntu), there are some rather striking differences. I'll
> start with some pgbench tests.

Is 3.2 a significant regression from previous releases, or is 3.4 just
faster? Your wording only indicates that "older kernel is slow," but
your tone would suggest that you feel this is a regression, cf. being
unhappy that 3.2 made its way into a LTS release (why wouldn't it? it
was a relatively current kernel at the time).

--
fdr