On Tue, Apr 28, 2009 at 5:58 PM, Scott Carey <scott@richrelevance.com> wrote:
> 1. If everything is on the same partition/file system, fsyncs from the
> xlogs may cross-pollute to the data. Ext3 is notorious for this, though
> data=writeback limits the effect you especially might not want
> data=writeback on your OS partition. I would recommend that the OS, Data,
> and xlogs + etc live on three different partitions regardless of the number
> of logical RAID volumes.
Note that I remember reading some comments a while back that just
having a different file system, on the same logical set, makes things
faster. I.e. a partition for OS, one for xlog and one for pgdata on
the same large logical volume was noticeably faster than having it all
on the same big partition on a single logical volume.
