Re: [HPDD-discuss] Lustre Pools vs Multiple Lustre File System recommendation
On 2014/07/21, 11:27 AM, "Robin Humble" <rjh+lustre(a)cita.utoronto.ca>
wrote:
On Mon, Jul 21, 2014 at 02:15:31PM +0000, Kumar, Amit wrote:
>Seeking for recommendations on setting up multiple Lustre file system
>"versus" creating multiple pools with exclusive OST's.
>
>We have two sets of disks SAS vs SATA and would like to separate them. I
>have created exclusive OST pools and they seem to work fine, but I am
>looking for recommendations before we go into production with this setup.
>We have 12 OSS and all of the SAS & SATA OST's are evenly spread across
>12 OSS's.
>
>Any thoughts on this is greatly appreciated.
I suspect you would get ~2x the iops if you used 2 fs's and 2 MDS's.
if you're already running an active/passive MDS pair then this would
mean no extra hardware.
That depends on where your bottleneck is. Yes, you would increase the
metadata ops/second, but you would only get 1/2 of your IO bandwidth for
each filesystem if you split the OSTs across two filesystems.
I think the one major limitation to using OST pools today is that they are
"advisory" only, and savvy users could specify any OST pool that they
want. That may be ok, but it depends on your users and environment.
We've discussed implementing usage quotas/limits on OST pools, but this
has not been implemented yet.
Cheers, Andreas
--
Andreas Dilger
Lustre Software Architect
Intel High Performance Data Division