From owner-freebsd-performance@FreeBSD.ORG Sat Jan 13 06:13:17 2007 Return-Path: X-Original-To: freebsd-performance@freebsd.org Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id B269516A412 for ; Sat, 13 Jan 2007 06:13:17 +0000 (UTC) (envelope-from markir@paradise.net.nz) Received: from smtp4.clear.net.nz (smtp4.clear.net.nz [203.97.37.64]) by mx1.freebsd.org (Postfix) with ESMTP id 75CFE13C428 for ; Sat, 13 Jan 2007 06:13:17 +0000 (UTC) (envelope-from markir@paradise.net.nz) Received: from [192.168.1.11] (121-72-72-39.dsl.telstraclear.net [121.72.72.39]) by smtp4.clear.net.nz (CLEAR Net Mail) with ESMTP id <0JBS00HJZMM1D930@smtp4.clear.net.nz> for freebsd-performance@freebsd.org; Sat, 13 Jan 2007 19:13:13 +1300 (NZDT) Date: Sat, 13 Jan 2007 19:13:12 +1300 From: Mark Kirkwood In-reply-to: <64656.200.152.83.36.1168651673.squirrel@webmail.matik.com.br> To: Michel Santos Message-id: <45A87878.1050505@paradise.net.nz> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit References: <64656.200.152.83.36.1168651673.squirrel@webmail.matik.com.br> User-Agent: Thunderbird 1.5.0.9 (X11/20061227) Cc: freebsd-performance@freebsd.org Subject: Re: diskio low read performance X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 13 Jan 2007 06:13:17 -0000 Michel Santos wrote: > I hope somebody can help me. I upgraded recently my cache server (squid) > 4.11 to 6.2 > > I notice that my disk read performance seems to be low. I observe it by > reading diskio from net-snmp. I started to check this because my old > server gave much better results from cache. > > I see read access as 1/4 - 1/6 of write access. My cache_dirs are full and > no swap in use. IOLA is not over 25-30 in peaks > > is there some special configuration to get better read performance on 6.2? > My disks are UW320 10k on Adaptec 29320 and the same as on the 4.11 > server. I really dont care about write speed so much so if there are > parameters to configure I apreciate to hear about. > > I checked the following with 1 and 0 but it does not make any difference > at all > > vfs.write_behind > vfs.vmiodirenable > > I get an average of 6-8Mb/s through this server and 3-4 of it is http > traffic. I see the object are going into the cache but for some reason it > seems they can not be read in time. > > I tried different newfs -b and -f and actually 1024/4096 seems to be best. > I do not cache large files on this machine. > > > Is there something I sgould try? > Note sure this will help you, as your files are all small, but try increasing vfs.read_max (say 16 or 32). Cheers Mark