Saturday, June 02, 2007

INNODB Disk setup and mount options



What Raid to use?

It's faster. RAID-5 offers more disk space but the parity bit messes things up, unless you have some uber hardware-raid card that caches that operation. Personally I am not a fan.

Stripe Size:
128K - this is really good for INNODB, you'll see a huge boost in responsiveness by making your Stripe Size 128K. I had a 64K stripe size, and I was blown away by the improvement of 128K

Mount options:

mkfs.ext3 -T largefile | mkfs.ext3 -T largefile4

Unless your going to have millions of files, this is a good option.

Make sure /etc/fstab mounts the mysql partition or the data that mysql resides on with noatime.

atime is accesstime: this is a huge boost in performance, tracking each time your ibdata file was last access is worthless, so don't do it.

From other benchmarks that I ran, I think that IBM's open source File system may be better then ext3 for certain workloads. Once I have more information I will post it here.


burtonator said...

Thanks for the 128k hint.. I'll have to try that ...

Also... ext3 and not XFS?

tanj said...

I'd go XFS over ext3 for performance.

Dathan said...

Using RHEL-4 doesn't support XFS, RHEL-5 - so for now I need to stick with ext3.

anne said...

La gran ventaja de los sistemas raid, pasa por la redundancia manteniendo los tiempos de transferencia, por eso los niveles 0 de raid no son los mas efectivos. Pero ojo, que a veces los raid fallan y la recuperaciĆ³n de sus datos se puede convertir en una pesadilla. Si en un momento dado necesitais recuperar datos de varios discos duros en raid os recomiendo las siguiente web :