From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (ext-mx13.extmail.prod.ext.phx2.redhat.com [10.5.110.18]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id p685N4kV030267 for ; Fri, 8 Jul 2011 01:23:04 -0400 Received: from Ishtar.tlinx.org (ishtar.tlinx.org [173.164.175.65]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p685N3xT019110 for ; Fri, 8 Jul 2011 01:23:04 -0400 Received: from [192.168.3.12] (Athenae [192.168.3.12]) by Ishtar.tlinx.org (8.14.4/8.14.4/SuSE Linux 0.8) with ESMTP id p685MrQ5021490 for ; Thu, 7 Jul 2011 22:22:55 -0700 Message-ID: <4E16942E.9070204@tlinx.org> Date: Thu, 07 Jul 2011 22:22:54 -0700 From: "Linda A. Walsh" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [linux-lvm] what use is virtualsize -- or how is it to be used? Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: LVM general discussion and development I just saw it in the man page, and first thing I tried was creating a logical volume by just giving a --virtualsize, arg -- thinking it would 'auto-extend it' as needed. Nep. Next was looking on the net and seeing an example that gave it some small size (-L 1G), with a virtual size of 2G. So what is that supposed to do? I just now thought to copy a bunch of files ( that differed from yesterday to today) to a tmp partition) but had it fail miserably when it REALLY failed upon reaching the physical limit -- not the virtual limit!).... I was trying to use rsync to copy from a snap from yesturday of /home that was mounted on /ohome to 'home.diff' (the partition that I used 'virtual size' with, ... I gave it a real size of 1G, and a virtual size of 1T. Using rsync, I had --compare-dest=/ohome (where I mount yesturday's snap) and copied from /home to /home.diff (the virtual partition).... Well the diffs were > 1G, so had hoped /home.diff would expand to it's virtual size... Anyway, got I/O errors, after I ran out of space. Ok, so *that*'s not what virtual size is for...either! Anyway, I unmounted the now 'corrupt' /home.diff, and tried to remove it... Got all sorts of i/o errors using lvremove Home.diff. (-f didn't work either). Got it to remove with lvremove -f /dev/PV/Home.diff That gave I/O errors too, but successfully completed... So what's virtual size good for, anyway?