Re: Strange behavior: pgbench and new Linux kernels

On Thu, 17 Apr 2008, Jeffrey Baker wrote:
> On Thu, Apr 17, 2008 at 12:58 AM, Greg Smith <gsmith(at)gregsmith(dot)com> wrote:
>> So in the case of this simple benchmark, I see an enormous performance
>> regression from the newest Linux kernel compared to a much older one.
>
> This has been discussed recently on linux-kernel. It's definitely a
> regression. Instead of getting a nice, flat overload behavior when
> the # of busy threads exceeds the number of CPUs, you get the
> declining performance you noted.
>
> Poor PostgreSQL scaling on Linux 2.6.25-rc5 (vs 2.6.22)
> http://marc.info/?l=linux-kernel&m=120521826111587&w=2

The last message in the thread says that 2.6.25-rc6 has the problem
nailed. That was a month ago. So I guess, upgrade to 2.6.25, which was
released today.

Matthew

--
"Prove to thyself that all circuits that radiateth and upon which thou worketh
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