Subject: Re: Adaptec AAA-131SA?
To: Jukka Marin <email@example.com>
From: Thor Lancelot Simon <firstname.lastname@example.org>
Date: 04/13/1999 14:47:42
On Tue, Apr 13, 1999 at 07:03:42PM +0300, Jukka Marin wrote:
> Is there / will there be support for the Adaptec RAID SCSI controllers
> AAA-131SA / AAA-131CA or AAA-33SA?
> Someone wants to build a reliable NetBSD system and they want to use RAID
> (and ECC RAM).
> (Yes, I know 1.4 supports RAID, but I haven't tried it out yet and this
> someone thinks there may be bugs in the new RAID implementation of NetBSD).
I haven't seen "bugs" in RAIDframe, FWIW -- but the performance is atrocious.
Try running a mirrored configuration sometime -- writes drop into the low tens
of kilobytes per second where the raw disks can do tens of megabytes.
There are various performance issues with the RAID 4 and RAID 5 modes but
I don't really have them pinned down well enough to say anything detailed.
In My Copious Free Time, I'm trying to sort out SCSI bus contention from
write size from RAIDframe configuration from... and then I'll do some
profiling, I think.
My vote? Buy a CMD CRD-5440 SCSI<->SCSI RAID controller and a pile of nice
disks (I like "Adjile", www.adjile.com, as a vendor) and put them on a good
SCSI adapter like a Qlogic ISP. If you really need more performance than
that, you can stripe multiple CMD's on multiple controllers -- the units
themselves are fault-tolerant, so it's safe to stripe them.
Obviously, since each RAID set then looks like a single SCSI disk, you can
boot from such a configuration...