Glyn Astill wrote:
--- On Sat, 22/11/08, Scott Marlowe <scott.marlowe@xxxxxxxxx> wrote:
You really have two choices. First is to try and use it as
a plain
SCSI card, maybe with caching turned on, and do the raid in
software.
Second is to cut it into pieces and make jewelry out of it.
Haha, I'm not really into jewelry, although I had thought of smacking it into a pile of dust with a lump hammer, that's much more my thing.
Anything
before the Perc 6 series is seriously brain damaged, and
the Perc6
brings the dell raid array line squarly in line with a 5
year old LSI
megaraid, give or take. And that's being generous.
Well this card thinks it's a 5 year old lsi megaraid. I've got a pile of perc5i megaraid paperweights on my desk at work, so this was kinda expected really.
I've tried writeback and write through modes,
tried changing cache flush times, disabled and enabled
multiple PCI delayed transactions, all seem to have little
effect.
Yeah, it's like trying to performance tune a yugo.
Did I mention I drive a yugo?
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.
Does it have a battery backup module? Often you can't
really turn on
write-back without one. That would certainly slow things
down. But
you should certainly expect > 20 M/s on a modern RAID
controller
writing out to a 4 disk RAID10
Yeah the battery's on it, that and the 128Mb is really the only reason I thought I'd give it a whirl.
Is the battery functioning? We found that the unit had to be on and charged before write back caching
would work.
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