Re: suggestions for postgresql setup on Dell 2950 , PERC6i controller

Scott Marlowe <scott.marlowe@gmail.com> writes:

> We purhcased the Perc 5E, which dell wanted $728 for last fall with 8
> SATA disks in an MD-1000 and the performance is just terrible.  No
> matter what we do the best throughput on any RAID setup was about 30
> megs/second write and 60 Megs/second read.

Is that sequential or a mix of random and sequential (It's too high to be
purely random i/o)? A single consumer drive should be able to beat those
numbers on sequential i/o. If it's a mix of random and sequential then
performance will obviously depend on the mix.

> I can get that from a mirror set of the same drives under linux kernel
> software RAID.

Why is that surprising? I would expect software raid to be able to handle 8
drives perfectly well assuming you had an controller and bus you aren't
saturating.

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  Gregory Stark
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