[Lustre-discuss] performance tuning

[Andreas Dilger]

On Jul 02, 2009  16:43 -0600, Martin Pokorny wrote:
>> - add more disks, or use SSD disks for the OSTs.  This will improve your
>>   IOPS rate dramatically.  It probably makes sense to create larger OSTs
>>   rather than many smaller OSTs due to less overhead (journal, connections,
>>   etc).
>
> I have been wondering about the effect SSD disks might have.  
> Unfortunately, for now, I need to show that it's worth my time to keep  
> working on a Lustre solution.

Another option, if you are using 1.8 is to enable the async journal
commit on the OSTs.  This can improve performance for small IO dramatically,
but is currently not supported in a production environment due to recovery
issues.  Since you are using a scratch filesystem only, you could do this
to test the performance.  It is "lctl set_param obdfilter.*.syncjournal=0"
on the OSTs.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.