Re: XFS filessystem for Datawarehousing

On Tue, Aug 01, 2006 at 08:42:23PM -0400, Alvaro Herrera wrote:
> J. Andrew Rogers wrote:
> >
> > On Aug 1, 2006, at 2:49 PM, Milen Kulev wrote:
> > >Is anyone using XFS for storing/retrieving relatively large amount
> > >of data (~ 200GB)?
> >
> >
> > Yes, we've been using it on Linux since v2.4 (currently v2.6) and it
> > has been rock solid on our database servers (Opterons, running in
> > both 32-bit and 64-bit mode). Our databases are not quite 200GB
> > (maybe 75GB for a big one currently), but ballpark enough that the
> > experience is probably valid. We also have a few terabyte+ non-
> > database XFS file servers too.
> >
> > Performance has been very good even with nearly full file systems,
> > and reliability has been perfect so far. Some of those file systems
> > get used pretty hard for months or years non-stop. Comparatively, I
> > can only tell you that XFS tends to be significantly faster than
> > Ext3, but we never did any serious file system tuning either.
>
> Most likely ext3 was used on the default configuration, which logs data
> operations as well as metadata, which is what XFS logs. I don't think
> I've seen any credible comparison between XFS and ext3 with the
> metadata-only journal option.
>
> On the other hand I don't think it makes sense to journal data on a
> PostgreSQL environment. Metadata is enough, given that we log data on
> WAL anyway.

Actually, according to http://en.wikipedia.org/wiki/Ext3 the default
journalling option for ext3 isn't to journal the data (which is actually
data=journal), but to wait until the data is written before considering
the metadata to be committed (data=ordered).
--
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