From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965255AbWFTKCT (ORCPT ); Tue, 20 Jun 2006 06:02:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965241AbWFTKCT (ORCPT ); Tue, 20 Jun 2006 06:02:19 -0400 Received: from p54AFEA14.dip.t-dialin.net ([84.175.234.20]:55941 "EHLO o.ww.redhat.com") by vger.kernel.org with ESMTP id S932572AbWFTKCS (ORCPT ); Tue, 20 Jun 2006 06:02:18 -0400 Date: Tue, 20 Jun 2006 12:02:09 +0200 From: Heinz Mauelshagen To: CaT Cc: linux-kernel@vger.kernel.org, dm-devel@redhat.com Subject: Re: 2.6.16.20/dm: can't create more then one snapshot of an lv Message-ID: <20060620100209.GA4566@redhat.com> Reply-To: mauelshagen@redhat.com References: <20060619020040.GX2059@zip.com.au> <20060620005405.GY2059@zip.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060620005405.GY2059@zip.com.au> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org How many snapshots active at once ? I guess this is a kcopyd scalability issue which needs addressing. Regards, Heinz -- The LVM Guy -- On Tue, Jun 20, 2006 at 10:54:05AM +1000, CaT wrote: > On Mon, Jun 19, 2006 at 12:00:40PM +1000, CaT wrote: > > I am attempting to create multiple snapshots of an lv ontop of a raid-5 > > software raid device and ext3+dir_index and resize_inode for the fs. > > The kernel is a pure 64bit compile with Debian Sarge amd64 running on > > top of it. The kernel is monolithic and I'm using lvm2 2.01.03-5 with > > devmapper 1.01. > > > > This works under 2.6.15.7. Under 2.6.16.20 I get this: > > 2.6.17 also fails. > > More info: The failing kernels can deal with multiple pre-created > snapshots but the moment I try to create one it freezes as below. Mounting > another snapshotted volume at the time this is frozen freezes mount. > > After reboot the snapshot it froze on making is available to the system > (though the reboot fails on shutdown as it cannot unmount anything). > > > # lvcreate --snapshot --size 50G --name snap-13 --permission r --verbose /dev/backups/main > > Setting chunksize to 16 sectors. > > Finding volume group "backups" > > Creating logical volume snap-13 > > Archiving volume group "backups" metadata. > > Creating volume group backup "/etc/lvm/backup/backups" > > Found volume group "backups" > > Loading backups-snap--13 > > Zeroing start of logical volume "snap-13" > > Found volume group "backups" > > Removing backups-snap--13 > > Found volume group "backups" > > Found volume group "backups" > > Found volume group "backups" > > Loading backups-main-real > > Loading backups-snap--12-cow > > Loading backups-snap--12 > > *freeze* > > -- > "To the extent that we overreact, we proffer the terrorists the > greatest tribute." > - High Court Judge Michael Kirby > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Heinz Mauelshagen Red Hat GmbH Consulting Development Engineer Am Sonnenhang 11 Storage Development 56242 Marienrachdorf Germany Mauelshagen@RedHat.com PHONE +49 171 7803392 FAX +49 2626 924446 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-