From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id n7PFqUSN211723 for ; Tue, 25 Aug 2009 10:52:41 -0500 Received: from mail.sandeen.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 7978C152E7F6 for ; Tue, 25 Aug 2009 08:52:58 -0700 (PDT) Received: from mail.sandeen.net (sandeen.net [209.173.210.139]) by cuda.sgi.com with ESMTP id l47JOrqv2Lz9Ab92 for ; Tue, 25 Aug 2009 08:52:58 -0700 (PDT) Message-ID: <4A9408C4.3050507@sandeen.net> Date: Tue, 25 Aug 2009 08:52:36 -0700 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: xfs logbufs default, (also noatime, lazy-count(of partition formatter)...32767b v. 32768b... References: <4A92E922.2030404@tlinx.org> In-Reply-To: <4A92E922.2030404@tlinx.org> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: "Linda A. Walsh" Cc: xfs-oss Linda A. Walsh wrote: > Is there a reason why logbufs=8 should't become the default? > Isn't it the best choice for most users given today's memory > constraints (or lack thereof?) It is the default: #define XLOG_MAX_ICLOGS 8 if (mp->m_logbufs <= 0) log->l_iclog_bufs = XLOG_MAX_ICLOGS; > I saw a message about xfs parameter tuning and still see the mention to: > 'logbufs=8,noatime' having to be specified on every mount. you can't believe everything you read on the internets ;) > If the desire is to provide default optimal tuning, maybe a default of > logbufs to 8 would be a good idea, and maybe a > mkfs flag to default to 'noatime' and a 64MB internal log > size would be good ideas for *most* users? noatime is something a user should choose based on their needs, not a default. Some things depend on atime, and noatime isn't really posix-compliant... Log size depends on the fs size... > How much of problem is defaulting to a 64MB internal log > size when file partitions are measured in the 100GB range? /* * With a 2GB max log size, default to maximum size * at 4TB. This keeps the same ratio from the older * max log size of 128M at 256GB fs size. IOWs, * the ratio of fs size to log size is 2048:1. */ 100*1024/2048 50 so it currently scales to 50M for 100G. > I'm not sure how much use it is to even remember typing lazy-count=1 > on the size partition each time. lazy-count will/should be the default soon; someone (me) just needs to make xfstests cope with the change first. > One more 'nit', while I think of it...for a 64MB log buffer size, > one should be able to specify 32768b, but last I tried, that gave > a 'too large' error...isn't 32768*4=64MB, not 32767b? seems fine? $ /sbin/mkfs.xfs -dfile,name=fsfile,size=100g -lsize=32768b meta-data=fsfile isize=256 agcount=4, agsize=6553600 blks = sectsz=512 attr=2 data = bsize=4096 blocks=26214400, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 log =internal log bsize=4096 blocks=32768, version=2 = sectsz=512 sunit=0 blks, lazy-count=0 realtime =none extsz=4096 blocks=0, rtextents=0 -Eric _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs