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Date: Sat, 22 Nov 2008 14:18:25 +0000 (GMT)
From: Glyn Astill <glynastill@yahoo.co.uk>
Reply-To: glynastill@yahoo.co.uk
Subject: Perc 3 DC
To: pgsql-performance@postgresql.org
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Message-ID: <680067.16755.qm@web23608.mail.ird.yahoo.com>

Hi chaps,

I've had this old card sitting on my desk for a while. It appears to be a U=
160 card with 128Mb BBU so I thought I'd wang it in my test machine (denian=
 etch) and give it a bash.

I set up 4 36Gb drives in raid 0+1, but I don't seem to be able to get more=
 than 20MB/s write speed out of it for large files (2XRAM usual tests with =
dd from dev/zero). I don't expect anything great, but I thought it'd do a l=
ittle better than that.

I've tried writeback and write through modes, tried changing cache flush ti=
mes, disabled and enabled multiple PCI delayed transactions, all seem to ha=
ve little effect.

Finally I decided to wave goodbye to Dell's firmware. LSI has it down as a =
MegaRAID 493 elite 1600, so I flashed it with their latest firmware.  Doesn=
't seem to have helped either though.

Has anybody else used this card in the past?  I'm wondering if this is a dr=
iver issue, or if the card is and always was just crap? If so I'll proababl=
y try sw raid on it instead.

Any thoughts?

Glyn=0A=0A=0A