Date:         Mon, 19 Sep 2005 23:01:43 -0700
Reply-To:     BruceBrad@INAME.COM
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Bruce Bradbury <BruceBrad@INAME.COM>
Organization: http://groups.google.com
Subject:      Re: recommendations for SAS PC configuration
Comments: To: sas-l@uga.edu
Content-Type: text/plain; charset="iso-8859-1"

For most SAS operations I/O is the bottleneck. I would put as much
money into the drives as possible. I've had good experiences with IDE
RAID 0 (eg a two-disk RAID 0 system almost doubled the throughput
speed). I would guess that RAID 5 would be just as fast reading.
Sustained transfer speed is the key (rather than seek times). You might
get more back for the buck using SATA than SCSI (particularly if the
machine won't be in continuous use).

When using RAID, I found best performance when I set bufsize and
ubufsize at twice the RAID stripe size (see Davis and Ralston
www2.sas.com/proceedings/sugi26/p277-26.pdf)

Bruce.

miskowski@gmail.com wrote:
> I'm specing out a system on Dell for a workstation that will crunch
> databases with up to about 10 million observations.  Will be using SAS.
>
> Looking at:
> Xeon 3.60 2mb L2 Cache (two of them)
> 2gig DDR2
> 19inch LCD (two of them)
> 128mb PCIe nVidia Quadro
> 73 gb ultra 320 SCSI 15,000rpm (three of them in RAID 5)
>
> I may end up increasing the HD's to 146gigs apiece, and perhaps
> decreasing the processor speed.  The above configuration come out to
> about $6000.  Planning on using winXP
>
> Where are the bottlnecks?  Are the SCSI drives overkill?  Will SATA in
> RAID be comparable?  Any suggestions would be appreciated.