Re: poor OCFS performance under Linux

As ocfs requires heartbeating (constant io), a slow io controller will hamper performance significantly.

Last I checked, qla2100 on rhel3 was problematic.

Try with a different io controller.

On Wed, 17 Mar 2004 14:08:42 -0800, Benjamin Wood wrote:

> I'm having tough time getting good IO performance utilizing OCFS under
> Linux.
>
> I have two x86 servers using QLA2100 cards against a 7 disk fibre
> array configured with software raid-0. The servers are running RHAS
> 3.0 2.4.21-4.EL, Oracle is 9.2.0.4, and OCFS is 1.0.10-1. OCFS was
> created with:
> mkfs.ocfs -F -b 128 -L /var/opt/oracle/oradata/orcl -m
> /var/opt/oracle/oradata/orcl -u `id -u oracle` -g `id -g oracle` -p
> 0775 /dev/md0
>
> I imported a 4 gig table and a count(*) utilizing a full table scan
> against it executed in about 120 seconds. Other operations big IO
> operations, (create datafiles, imports, intensive queries) ran slowly,
> with top indicating about 80% IO wait time.
>
> I configured another database (single node) with identical
> hardware/OS/Oracle/OCFS, utilizing EXT2 and the same query ran in 30
> seconds (same execution plan) and everything was far quicker. For
> kicks, I reformatted the datafile partition to OCFS and things were
> back to running slow on this single node environment. OCFS seems to
> be the weak link here, or at least my implementation of it.
>
> I must be missing something, but scouring the Metalink groups and
> Google didn't come up with anything that's helped...
>
> Many thanks,
> Benjamin
Received on Wed Mar 24 2004 - 20:11:04 CST