X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 88A499DCC84 for ; Mon, 20 Mar 2006 19:26:38 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 13321-05 for ; Mon, 20 Mar 2006 19:26:40 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from peufeu.com (boutiquenumerique.com [82.67.9.10]) by postgresql.org (Postfix) with ESMTP id 21DF29DCBB2 for ; Mon, 20 Mar 2006 19:26:35 -0400 (AST) Received: (qmail 21371 invoked from network); 21 Mar 2006 00:27:05 +0100 Received: from boutiquenumerique.com (HELO apollo13) (82.67.9.10) by boutiquenumerique.com with SMTP; 21 Mar 2006 00:27:05 +0100 Date: Tue, 21 Mar 2006 00:27:04 +0100 To: "Postgresql Performance" Subject: Re: Best OS & Configuration for Dual Xeon w/4GB & Adaptec References: <20060317221116.GA14661@juniper.net> <8F6490E1-64E2-406B-A559-7DA8BA1EB197@khera.org> <441F161D.7010502@123.com.sv> From: PFC Content-Type: text/plain; format=flowed; delsp=yes; charset=utf-8 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID: In-Reply-To: <441F161D.7010502@123.com.sv> User-Agent: Opera M2/8.51 (Linux, build 1462) X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.111 required=5 tests=[AWL=0.111] X-Spam-Score: 0.111 X-Spam-Level: X-Archive-Number: 200603/358 X-Sequence-Number: 17795 This is a 2-Disk Linux software RAID1 with 2 7200RPM IDE Drives, 1 PATA and 1 SATA : apollo13 ~ # hdparm -t /dev/md0 /dev/md0: Timing buffered disk reads: 156 MB in 3.02 seconds = 51.58 MB/sec apollo13 ~ # hdparm -t /dev/md0 /dev/md0: Timing buffered disk reads: 168 MB in 3.06 seconds = 54.87 MB/sec This is a 5-Disk Linux software RAID5 with 4 7200RPM IDE Drives and 1 5400RPM, 3 SATA and 2 PATA: apollo13 ~ # hdparm -t /dev/md2 /dev/md2: Timing buffered disk reads: 348 MB in 3.17 seconds = 109.66 MB/sec apollo13 ~ # hdparm -t /dev/md2 /dev/md2: Timing buffered disk reads: 424 MB in 3.00 seconds = 141.21 MB/sec apollo13 ~ # hdparm -t /dev/md2 /dev/md2: Timing buffered disk reads: 426 MB in 3.00 seconds = 141.88 MB/sec apollo13 ~ # hdparm -t /dev/md2 /dev/md2: Timing buffered disk reads: 426 MB in 3.01 seconds = 141.64 MB/sec The machine is a desktop Athlon 64 3000+, buggy nforce3 chipset, 1G DDR400, Gentoo Linux 2.6.15-ck4 running in 64 bit mode. The bottleneck is the PCI bus. Expensive SCSI hardware RAID cards with expensive 10Krpm harddisks should not get humiliated by such a simple (and cheap) setup. (I'm referring to the 12-drive RAID10 mentioned before, not the other one which was a simple 2-disk mirror). Toms hardware benchmarked some hardware RAIDs and got humongous transfer rates... hm ?