Re: moving pg_xlog -- yeah, it's worth it!

Kevin Grittner wrote:
> Jesper Krogh <jesper@krogh.cc> wrote:
>
> > Sorry if it is obvious.. but what filesystem/OS are you using and
> > do you have BBU-writeback on the main data catalog also?
>
> Sorry for not providing more context.
>
> ATHENA:/var/pgsql/data # uname -a
> Linux ATHENA 2.6.16.60-0.39.3-smp #1 SMP Mon May 11 11:46:34 UTC
> 2009 x86_64 x86_64 x86_64 GNU/Linux
> ATHENA:/var/pgsql/data # cat /etc/SuSE-release
> SUSE Linux Enterprise Server 10 (x86_64)
> VERSION = 10
> PATCHLEVEL = 2
>
> File system is xfs noatime,nobarrier for all data; OS is on ext3.  I
> *think* the pg_xlog mirrored pair is hanging off the same
> BBU-writeback controller as the big RAID, but I'd have to track down
> the hardware tech to confirm, and he's out today.  System has 16
> Xeon CPUs and 64 GB RAM.

I would be surprised if the RAID controller had a BBU-writeback cache.
I don't think having xlog share a BBU-writeback makes things slower, and
if it does, I would love for someone to explain why.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +