GFS, OCFS, and GPFS - Which Filesystem for Oracle?
amani asks: "My company has a Oracle 9i RAC database running on a Sun cluster. In 6 months we are looking to replace the cluster with either a Linux or an AIX solution that will involve SAN storage. I see that their are a variety of filesystems for Oracle and Linux. Sistina (Red Hat) has the GFS, Oracle has the OCFS, and IBM has GPFS. Does anyone know the pros and cons of each of these filesystems ,and which one would be better for a continuously growing database?"
Have you looked at a Veritas Cluster? (VCS) The company I work for uses it and we have found it to be very stable.
As someone involved in building and architecting ludicrously sized realtime transaction processing systems, I can honestly tell you that the answer is "whatever".
If you have lots more updates than accesses, you need your redo logs etc on RAW devices, no filesystem required, these will be your biggest bottleneck. The rest, well, just go for a decent hardware RAID implementation, since software RAID is a joke.
If you have lots more accesses than updates then it's your RAM which will probably make the real impact.
And at the end of the day, if you're looking at advice, and you're sporting a cheque in your pocket - ask the vendors to tell you which one you should buy! Ask the tricky questions and put their answers in your contract so that they pay you if they lie
I know - it's a nice dream.
/* affect != effect */ void affect(int *thing,int effect) { *thing += effect; }
Um.. perhaps call your Oracle support people. If your company is at all sizable, they probably have support contracts with the companies that provide them their mission-critical software? And their professional services/technical engineering people would surely be the best people to ask.
Despite all the wisecracks about the name, our sentimental favorite should be GPFS because of a certain well known geek who works for the filesystem group at IBM Almaden.
What about Lustre (http://www.lustre.org)?
BTW, implicitly, closed != bad. Yes, sometimes it does, but not always.
Also, by what definition is a filesystem a "cluster filesystem". One in which the cluster nodes can (a) access, (b) provide or (c) access and provide the filesystem? Not every flavour of clustered filesystem falls in the same category.
I do agree with the license comment on closed source systems - the per-node license fees are ridiculous.
The real question is, why are you migrating your hardware? Is it because you want to save some money on infrastructure in the short term? Is it because you're thinking long-term and are worried about the viability of the Sun platform? Is it because performance and/or reliability aren't good enough with your present system? Is it because your company has been acquired and your new owners are in bed with IBM? Or is it because Linux is the buzzword of the day and your boss insists you use it? Forgive my nosiness, but they question you are asking isn't really a tech question that has a straightforward answer. What is the outcome you are looking for? A wise engineer chooses his tools according to the job at hand, not the other way round.
Figure out what you want to accomplish, then figure out what you need to do that. It's easy enough to try all three and see...