Re: disk performance benchmarks

>>>>> "SW" == Shane Wright <Shane> writes:

SW> But, we have now taken the plunge and I'm in a position to do some
SW> benchmarking to actually get some data. Basically I was wondering if
SW> anyone else had any particular recommendations (or requests) about the
SW> most useful kinds of benchmarks to do.

I did a bunch of benchmarking on a 14 disk SCSI RAID array comparing
RAID 5, 10, and 50. My tests consisted of doing a full restore of a
30Gb database (including indexes) and comparing the times to do the
restore, the time to make the indexes, and the time to vacuum. Then I
ran a bunch of queries.

It was damn near impossible to pick a 'better' RAID config, so I just
went with RAID5.

You can find many of my posts on this topic on the list archives from
about august - october of last year.

Basically, you have to approach it holistically to tune the system: Pg
config parameters, memory, and disk speed are the major factors.

That and your schema needs to be not idiotic. :-)

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