FW: pg_xlog on data partition with BBU RAID

Forwarding to -performance

From: Alan Hodgson [mailto:ahodgson@simkin.ca]

On Friday 09 June 2006 12:41, "Jim C. Nasby" <jnasby@pervasive.com> wrote:
> Has anyone actually done any testing on this? Specifically, I'm
> wondering if the benefit of adding 2 more drives to a RAID10 outweighs
> whatever penalties there are to having pg_xlog on that RAID10 with all
> the rest of the data.

I have an external array with 1GB of write-back cache, and testing on it
before deployment showed no difference under any workload I could generate
between having pg_xlog on a separate RAID-1 or having it share a RAID-10
with the default tablespace.  I left it on the RAID-10, and it has been
fine there.  We have a very write-heavy workload.

--
"If a nation expects to be ignorant and free, in a state of civilization,
it expects what never was and never will be." -- Thomas Jefferson