20040730: BOUNCE ldm-users@unidata.ucar.edu: Non-member submission from [Robert Mullenax <rmullenax@impactweather.com>]

[Unidata Support <support@xxxxxxxxxxxxxxxx>]

>From: owner-ldm-users@xxxxxxxxxxxxxxxx
>Organization: UCAR/Unidata
>Keywords: 200407302213.i6UMDRLW023442

Hi Robert,

Your email to the ldm-users email list regarding software RAID bounced
since the email address you sent the inquiry from:

rmullenax@xxxxxxxxxxxxxxxxx

was not subscribed to the list.  I just approved your subscriptions
to the gembud, ldm-users, mcidas-x, pc-os, and nws-changes lists,
so you could resend your inquiry if you like.

Besides that, I have done a lot of investigation into use of software
RAID under Linux on machines running the LDM.  The last system I worked
on not at the UPC was Gerry Creager's dual Xeon 2.4 Ghz machine that
uses two HighPoint raid controllers (each has 4 IDE channels) and
8 Maxtor 250 GB (7200 RPM 2 MB cache) disks.  After Gerry spent quite
a bit of time trying to get hardware RAID to work correctly (i.e., the
machine not crash), he came over to my way of thinking and tried
software RAID.  He played with several file systems on the RAID (ext3,
jfs come to mind) before settling on ext2 even though it is not a
journaling file system.  He set the block size at 4 KB which I thought
was too small, but the performance of the RAID has made me think
otherwise.

Gerry was also using his machine as an NFS server for awhile, but
I don't know if he is doing that anymore.

If you want to contact Gerry directly, his email address is:

Gerry Creager n5jxs <gerry.creager@xxxxxxxx>

Cheers,

Tom

>From support@xxxxxxxxxxxxxxxx Fri Jul 30 16:13:26 2004
>Received: from uwxcom01.univ-wea.com (uwxcom01.univ-wea.com [12.31.213.84])
>	by unidata.ucar.edu (UCAR/Unidata) with ESMTP id i6UMDPaW023436
>	for <ldm-users@xxxxxxxxxxxxxxxx>; Fri, 30 Jul 2004 16:13:25 -0600 (MDT)
>Organization: UCAR/Unidata
>Keywords: 200407302213.i6UMDPaW023436
>Received: from houmm.nt.univ-wea.com (houmm.univ-wea.com [12.31.213.144])
>	by uwxcom01.univ-wea.com (8.12.10/8.12.10) with ESMTP id i6UMCma5027592
>	for <ldm-users@xxxxxxxxxxxxxxxx>; Fri, 30 Jul 2004 22:12:58 GMT
>Received: from LIGHTNING.univ-wea.com (Not Verified[12.31.213.81]) by houmm.nt
> .univ-wea.com with NetIQ MailMarshal (v5.5.6.7)
>	id <B00035b856>; Fri, 30 Jul 2004 17:12:48 -0500
>Received: by lightning.univ-wea.com with Internet Mail Service (5.5.2653.19)
>	id <3V0M5JC2>; Fri, 30 Jul 2004 17:06:24 -0500
>Message-ID: <69D72311B46FD4119EF100D0B77CF7DA0F08F751@xxxxxxxxxxxxxxxxxxxxxx>
>From: Robert Mullenax <rmullenax@xxxxxxxxxxxxxxxxx>
>To: "'ldm-users@xxxxxxxxxxxxxxxx'" <ldm-users@xxxxxxxxxxxxxxxx>
>Subject: LDM and SW RAID
>Date: Fri, 30 Jul 2004 17:06:21 -0500
>MIME-Version: 1.0
>X-Mailer: Internet Mail Service (5.5.2653.19)
>Content-Type: text/plain
>
>Could someone that is using software RAID on an LDM box that acts
>as an NFS server e-mail offline?   I have some performance questions.
>Basically I am seeing very slow reads from a 5 disk stripe (16K)
>on SW RAID 0 as compared to a single disk. 
>
>
>Thanks,
>Robert Mullenax
>
--
NOTE: All email exchanges with Unidata User Support are recorded in the
Unidata inquiry tracking system and then made publically available
through the web.  If you do not want to have your interactions made
available in this way, you must let us know in each email you send to us.