X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (mx1.hub.org [200.46.208.251]) by postgresql.org (Postfix) with ESMTP id 8805511F6067 for ; Sat, 29 Apr 2006 02:07:47 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.208.251]) (amavisd-new, port 10024) with ESMTP id 80050-01 for ; Sat, 29 Apr 2006 02:07:41 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- Received: from mail.mi8.com (d01gw02.mi8.com [63.240.6.46]) by postgresql.org (Postfix) with ESMTP id 51AE711F6031 for ; Sat, 29 Apr 2006 02:07:39 -0300 (ADT) Received: from 172.16.1.110 by mail.mi8.com with ESMTP (- Welcome to Mi8 Corporation www.Mi8.com (D2)); Sat, 29 Apr 2006 01:07:34 -0400 X-Server-Uuid: 7829E76E-BB9E-4995-8473-3C0929DF7DD1 Received: from MI8NYCMAIL06.Mi8.com ([172.16.1.160]) by D01SMTP01.Mi8.com with Microsoft SMTPSVC(6.0.3790.1830); Sat, 29 Apr 2006 01:07:34 -0400 Received: from 69.181.100.71 ([69.181.100.71]) by MI8NYCMAIL06.Mi8.com ( [172.16.1.219]) via Exchange Front-End Server mi8owa.mi8.com ( [172.16.1.107]) with Microsoft Exchange Server HTTP-DAV ; Sat, 29 Apr 2006 05:07:33 +0000 User-Agent: Microsoft-Entourage/11.2.3.060209 Date: Fri, 28 Apr 2006 22:07:29 -0700 Subject: Re: hardare config question From: "Luke Lonergan" To: erik.myllymaki@aviawest.com, pgsql-performance@postgresql.org Message-ID: Thread-Topic: [PERFORM] hardare config question Thread-Index: AcZq4BnYGK5LqRepSyGYyH0NRnhU2wAarZEs In-Reply-To: <445236D5.5060509@aviawest.com> MIME-Version: 1.0 X-OriginalArrivalTime: 29 Apr 2006 05:07:34.0246 (UTC) FILETIME=[D33E3860:01C66B4A] X-WSS-ID: 684C2B1C20K283343-01-01 Content-Type: multipart/alternative; boundary=B_3229106850_7112162 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200604/687 X-Sequence-Number: 18771 > This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --B_3229106850_7112162 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Erik, I think you have a mismatch in your Linux driver and firmware for your 3Ware card. Download a matched Linux driver and firmware from www.3ware.com and your problems should disappear. - Luke On 4/28/06 8:37 AM, "Erik Myllymaki" wrote: > This is a question that I also posted on Dell hardware forums, and I realize > it > probably belongs there more than here. But I am thinking someone might have > some anecdotal information that could help me and this post may help someone > else down the road. > > My PowerEdge 1800 (dual 3ghz Xeon, 3GB ram) came with a single SATA drive. I > installed and developed a modest database application (Postgresql, Windows > 2003 > Server, Python) on it and was pretty impressed with the performance. > > I wanted to add some more space, speed and reliability so I bought a used > 3ware > 9500s SATA raid card. I bought three more of the same drives (Seagate > ST3808110as) and configured them in RAID 5 (3 in RAID one as hot spare). I > reinstalled the OS and software (my efforts to ghost were not > fruitful...another story), and the first thing I did was run a sql script to > make tables, indexes, sequences etc for my app and import about 20MB of data. > > When I had this installed on a single SATA drive running from the PE1800's > on-board SATA interface, this operation took anywhere from 65-80 seconds. > > With my new RAID card and drives, this operation took 272 seconds!? > > I did a quick search and found a few posts about how RAID 5 with Databases is > a > poor choice and one in particular about Postgres and how you could expect > performance to be halved with RAID 5 over a single drive or RAID 1 (until you > get above 6 disks in your RAID 5 array). So, a poorly planned configuration on > my part. > > I scrubbed the RAID config, made two RAID 1 containers (also read about how > moving database logs to a different partition than the database data is > optimal > for speed and reliability). I installed the OS on the first RAID 1 volume, the > Postgresql apps and data on the other, and used Junction from sysinternals to > put the pg_xlogs back on the OS partition (does Postgresql have an easier way > to do this on Windows?). > > Well, things didn't improve noticeably - 265 seconds. > > Next step, turn on the 3ware RAID card's write cache (even though I have no > Battery Backup Unit on the RAID card and am warned about possible data loss in > the event of power loss). > > This helped - down to 172 seconds. > > Is this loss in performance just the normal overhead involved when adding a > raid card - writes now having to go to two drives instead of one? Or maybe is > the SATA interface on the Dell 1800s motherboard faster than the interface on > the 3ware raid card (SATA II ?). > > Thanks for any help you guidance you can provide. > > ---------------------------(end of broadcast)--------------------------- > TIP 3: Have you checked our extensive FAQ? > > http://www.postgresql.org/docs/faq > > --B_3229106850_7112162 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: quoted-printable Re: [PERFORM] hardare config question Erik,=

I think you have a mismatch in your Linux driver and firmware for your 3War= e card.  Download a matched Linux driver and firmware from www.3ware.co= m and your problems should disappear.

- Luke


On 4/28/06 8:37 AM, "Erik Myllymaki" <erik.myllymaki@aviawest.= com> wrote:

This is a question that I also posted on Dell hardware = forums, and I realize it
probably belongs there more than here. But I am thinking someone might have=
some anecdotal information that could help me and this post may help someon= e
else down the road.

My PowerEdge 1800 (dual 3ghz Xeon, 3GB ram) came with a single SATA drive. = I
installed and developed a modest database application (Postgresql, Windows = 2003
Server, Python) on it and was pretty impressed with the performance.

I wanted to add some more space, speed and reliability so I bought a used 3= ware
9500s SATA raid card. I bought three more of the same drives (Seagate
ST3808110as) and configured them in RAID 5 (3 in RAID one as hot spare). I<= BR> reinstalled the OS and software (my efforts to ghost were not
fruitful...another story), and the first thing I did was run a sql script t= o
make tables, indexes, sequences etc for my app and import about 20MB of dat= a.

When I had this installed on a single SATA drive running from the PE1800's<= BR> on-board SATA interface, this operation took anywhere from 65-80 seconds.
With my new RAID card and drives, this operation took 272 seconds!?

I did a quick search and found a few posts about how RAID 5 with Databases = is a
poor choice and one in particular about Postgres and how you could expect performance to be halved with RAID 5 over a single drive or RAID 1 (until y= ou
get above 6 disks in your RAID 5 array). So, a poorly planned configuration= on
my part.

I scrubbed the RAID config, made two RAID 1 containers (also read about how=
moving database logs to a different partition than the database data is opt= imal
for speed and reliability). I installed the OS on the first RAID 1 volume, = the
Postgresql apps and data on the other, and used Junction from sysinternals = to
put the pg_xlogs back on the OS partition (does Postgresql have an easier w= ay
to do this on Windows?).

Well, things didn't improve noticeably - 265 seconds.

Next step, turn on the 3ware RAID card's write cache (even though I have no=
Battery Backup Unit on the RAID card and am warned about possible data loss= in
the event of power loss).

This helped - down to  172 seconds.

Is this loss in performance just the normal overhead involved when adding a=
raid card - writes now having to go to two drives instead of one? Or maybe = is
the SATA interface on the Dell 1800s motherboard faster than the interface = on
the 3ware raid card (SATA II ?).

Thanks for any help you guidance you can provide.

---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ?

            &nb= sp;  http://www.postg= resql.org/docs/faq



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