From owner-freebsd-questions@FreeBSD.ORG Fri Aug 17 20:17:09 2007 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id DE55416A417 for ; Fri, 17 Aug 2007 20:17:09 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from mail-out3.apple.com (mail-out3.apple.com [17.254.13.22]) by mx1.freebsd.org (Postfix) with ESMTP id C535C13C468 for ; Fri, 17 Aug 2007 20:17:09 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from relay7.apple.com (relay7.apple.com [17.128.113.37]) by mail-out3.apple.com (Postfix) with ESMTP id 926CEEC4F21; Fri, 17 Aug 2007 13:17:09 -0700 (PDT) Received: from relay7.apple.com (unknown [127.0.0.1]) by relay7.apple.com (Symantec Mail Security) with ESMTP id 7E13C300C6; Fri, 17 Aug 2007 13:17:09 -0700 (PDT) X-AuditID: 11807125-a121cbb0000007e5-5f-46c602455dab Received: from [17.214.13.96] (cswiger1.apple.com [17.214.13.96]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by relay7.apple.com (Apple SCV relay) with ESMTP id 7051B30002; Fri, 17 Aug 2007 13:17:09 -0700 (PDT) In-Reply-To: <4B90A9A7-D8D6-49C5-B097-00094486EF4A@messier.com> References: <4B90A9A7-D8D6-49C5-B097-00094486EF4A@messier.com> Mime-Version: 1.0 (Apple Message framework v752.2) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: <0CB0F62F-8071-4CAE-BFE7-6ECCBE701678@mac.com> Content-Transfer-Encoding: 7bit From: Chuck Swiger Date: Fri, 17 Aug 2007 13:17:08 -0700 To: Mark Messier X-Mailer: Apple Mail (2.752.2) X-Brightmail-Tracker: AAAAAA== Cc: FreeBSD Mailing List Subject: Re: performance hints (6.2) X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 17 Aug 2007 20:17:10 -0000 On Aug 17, 2007, at 1:00 PM, Mark Messier wrote: > I've got a freebsd 6.2 system, dual 2Ghz 5130 cpu, 4g ram, with raid5 > Adaptec 2120s, running not much more than /usr/ports/mail/imap-uw > and I'm having performance problems with only 20 IMAP users. > > I'm not swapping.. cpu is mostly idle, so I figure it must be I/O > performance. Just to confirm, is that what the following show? You're seeing upwards of 400 I/O transactions per sec, so your system is definitely I/O bound. Note that RAID-5 is not an ideal choice for a filesystem which is going to be used for balanced read-write operations-- it's best used for read-only or read-mostly purposes. You are probably using the default mbox mail format; you're likely to find that using maildir would work much better when running on a RAID-5 volume. Regards, -- -Chuck