Subject: Re: getting count for a specific querry
From: Scott Marlowe <smarlowe@g2switchworks.com>
To: Bob Henkel <luckyratfoot@gmail.com>
Cc: Vivek Khera <vivek@khera.org>, pgsql-sql@postgresql.org
In-Reply-To: <762e5c05040813354436bd27@mail.gmail.com>
References: <003b01c53c70$6ff184b0$797ba8c0@jfradkin>
	<cb3b9f9319ae75a9f8eb756ff38e85e8@khera.org>
	<762e5c05040813354436bd27@mail.gmail.com>
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Date: Fri, 08 Apr 2005 15:42:01 -0500

On Fri, 2005-04-08 at 15:35, Bob Henkel wrote:
> On Apr 8, 2005 3:23 PM, Vivek Khera <vivek@khera.org> wrote: 
>         On Apr 8, 2005, at 3:23 PM, Joel Fradkin wrote:
>         
>         > I set up the data on 4 10k scsi drives in a powervault and
>         my wal on 2
>         > 15k
>         > drives. I am using links to those from the install
>         directory. It
>         > starts and
>         > stops ok this way, but maybe it should be different.
>         >
>         
>         Your problem might just be the choice of using a Dell RAID
>         controller.
>         I have a 1 year old box connected to a 14 disk powervault
>         (PowerEdge
>         2650) and it is dog slow compared to a dual opteron with 8
>         disks that
>         is replacing it.  It is all I/O for me, and the dell's just
>         are not
>         known for speedy I/O.
>         
>         Vivek Khera, Ph.D.
>         +1-301-869-4449 x806
>         
>         
> 
> But that is relative I would think.  Is the Dell RAID much faster than
> my desktop SATA drive with no RAID? I'm by any means as knowledgeable
> about I/O setup as many of you are but my 2 cents wonders if the Dell
> RAID is really that much slower than a competitively priced/speced
> alternative?  Would Joel's problems just fade away if he wasn't using
> a Dell RAID? 

My experience with the 3i controllers (See my earlier post) was that my
old Pentium Pro200x2 machine with 512 meg ram and a generic Ultra Wide
SCSI card and a half dozen drives running software RAID 5 was faster.

Seriously.  So was my P-II-350 desktop with the same controller, and an
older Dual P-III-750 with only UltraSCSI running in a RAID-1 mirror set.

The 3I is REALLY slow (or at least WAS slow) under linux.