Kevin Grittner wrote:
> Another example of why I shouldn't trust my memory. Per the
> hardware tech:
>
>
> OS: /dev/sda is RAID1 - 2 x 2.5" 15k SAS disk
> pg_xlog: /dev/sdb is RAID1 - 2 x 2.5" 15k SAS disk
>
> These reside on a ServeRAID-MR10k controller with 256MB BB cache.
>
>
> data: /dev/sdc is RAID5 - 30 x 3.5" 15k SAS disk
>
> These reside on the DS3200 disk subsystem with 512MB BB cache per
> controller and redundant drive loops.
Hmm, so maybe the performance benefit is not from it being on a separate
array, but from it being RAID1 instead of RAID5?
--
Alvaro Herrera http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support