Date: Tue, 05 Dec 2006 07:15:09 -0500
From: Michael Stone <mstone+postgres@mathom.us>
Subject: Re: Bad iostat numbers
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On Tue, Dec 05, 2006 at 01:21:38AM -0500, Alex Turner wrote:
>My other and most important point is that I can't find any solid
>recommendations for a SCSI card that can perform optimally in Linux or
>*BSD.  Off by a factor of 3x is pretty sad IMHO. (and yes, we know the
>Adaptec cards suck worse, that doesn't bring us to a _good_ card).

This gets back to my point about terminology. As a SCSI HBA the Adaptec 
is decent: I can sustain about 300MB/s off a single channel of the 
39320A using an external RAID controller. As a RAID controller I can't 
even imagine using the Adaptec; I'm fairly certain they put that 
"functionality" on there just so they could charge more for the card. It 
may be that there's not much market for on-board SCSI RAID controllers; 
between SATA on the low end and SAS & FC on the high end, there isn't a
whole lotta space left for SCSI. I definitely don't think much
R&D is going into SCSI controllers any more, compared to other solutions 
like SATA or SAS RAID (the 39320 hasn't change in at least 3 years, 
IIRC). Anyway, since the Adaptec part is a decent SCSI controller and a 
lousy RAID controller, have you tried just using software RAID? 

Mike Stone