From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id 0EC3D7F51 for ; Thu, 29 Aug 2013 20:44:28 -0500 (CDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay2.corp.sgi.com (Postfix) with ESMTP id E3FA6304039 for ; Thu, 29 Aug 2013 18:44:24 -0700 (PDT) Received: from greer.hardwarefreak.com (mo-65-41-216-221.sta.embarqhsd.net [65.41.216.221]) by cuda.sgi.com with ESMTP id 3ghVrtdF9NNmIBVQ for ; Thu, 29 Aug 2013 18:44:24 -0700 (PDT) Message-ID: <521FF8F4.9040009@hardwarefreak.com> Date: Thu, 29 Aug 2013 20:44:20 -0500 From: Stan Hoeppner MIME-Version: 1.0 Subject: Re: higher agcount on LVM2 thinp volumes References: <321D1F95-5603-4571-A445-A267DA5F670F@colorremedies.com> In-Reply-To: <321D1F95-5603-4571-A445-A267DA5F670F@colorremedies.com> Reply-To: stan@hardwarefreak.com List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Chris Murphy Cc: xfs@oss.sgi.com On 8/29/2013 1:09 AM, Chris Murphy wrote: > > Is it expected when formatting, using defaults, that a thinp volume compared to either a conventional LV or partition of the same size, should have a higher agcount? > > > HDD, GPT partitioned, 100GB partition size: > > [root@f19s ~]# mkfs.xfs /dev/sda7 > meta-data=/dev/sda7 isize=256 agcount=4, agsize=6553600 blks > = sectsz=512 attr=2, projid32bit=0 > 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=12800, version=2 > = sectsz=512 sunit=0 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > > > A 400GB partition, made into PV, PV added to VG, and all extents put into a thinpool volume, a 100GB virtual sized LV: > > [root@f19s ~]# mkfs.xfs /dev/mapper/vg1-data > meta-data=/dev/mapper/vg1-data isize=256 agcount=16, agsize=1638400 blks > = sectsz=512 attr=2, projid32bit=0 > 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=12800, version=2 > = sectsz=512 sunit=0 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > > > > I get agcount=4 on a conventional LV as well. Why agcount=16 on thinp? More information would be helpful, specifically WRT the device stack underlying mkfs.xfs. I.e. we need to know more about the LVM configuration. See: http://xfs.org/index.php/XFS_FAQ#Q:_What_information_should_I_include_when_reporting_a_problem.3F -- Stan _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs