Re: Running on an NFS Mounted Directory

On Thu, Apr 27, 2006 at 08:57:51AM -0400, Ketema Harris wrote:
> OK. My thought process was that having non local storage as say a big raid
> 5 san ( I am talking 5 TB with expansion capability up to 10 ) would allow
> me to have redundancy, expandability, and hopefully still retain decent
> performance from the db. I also would hopefully then not have to do
> periodic backups from the db server to some other type of storage. Is this
> not a good idea? How bad of a performance hit are we talking about? Also,
> in regards to the commit data integrity, as far as the db is concerned once
> the data is sent to the san or nas isn't it "written"? The storage may have
> that write in cache, but from my reading and understanding of how these
> various storage devices work that is how they keep up performance. I would
> expect my bottleneck if any to be the actual Ethernet transfer to the
> storage, and I am going to try and compensate for that with a full gigabit
> backbone.

Well, if you have to have both the best performance and remote attach
storage, I think you'll find that a fibre-channel SAN is still the king
of the hill. 4Gb FC switches are common now, though finding a 4Gb
HBA for your computer might be a trick. 2Gb HBAs are everywhere in
FC land. That's a premium price solution, however, and I don't know
anything about how well PG would perform with a FC SAN. We use our
SAN for bulk science data and leave the PGDB on a separate machine
with local disk.

--
Steve Wampler -- swampler(at)noao(dot)edu
The gods that smiled on your birth are now laughing out loud.