Re: RAID0 and pg_xlog

On Wed, Sep 07, 2005 at 01:02:18PM -0500, Scott Marlowe wrote:
> On Wed, 2005-09-07 at 12:40, Jim C. Nasby wrote:
> > On Wed, Sep 07, 2005 at 12:47:43PM -0700, Qingqing Zhuo wrote:
> > > Xlog will be the only believable data if your system crashed. So it is a dangerous practice to put xlog stuff in RAID0.
> >
> > No more or less so than putting your main database on RAID0. If any
> > drive fails, you lose everything.
>
> Sounds like a good place to have replication.

If you used syncronous replication, maybe. Otherwise failure of any
drive means you just lost data. And remember that the more drives you
have in your array the more likely you'll have a failure in a given
time period.

Basically, if you can afford to setup replication on 2 machines with
RAID0 you can afford to setup RAID10 on one machine, which will usually
be a better bet.
--
Jim C. Nasby, Sr. Engineering Consultant jnasby(at)pervasive(dot)com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461