Re: feature request: btrfs-image without zeroing data
2011-07-11 02:00:51 +0200, krz...@gmail.com : Documentation says that btrfs-image zeros data. Feature request is for disabling this. btrfs-image could be used to copy filesystem to another drive (for example with snapshots, when copying it file by file would take much longer time or acctualy was not possible (snapshots)). btrfs-image in turn could be used to actualy shrink loop devices/sparse file containing btrfs - by copying filesystem to new loop device/sparse file. Also it would be nice if copying filesystem could occour without intermediate dump to a file... [...] I second that. See also http://thread.gmane.org/gmane.comp.file-systems.btrfs/9675/focus=9820 for a way to transfer btrfs fs. (Add a layer of copy-on-write on the original devices (LVM snapshots, nbd/qemu-nbd cow...), btrfs add the new device(s) and then btrfs del of the cow'ed original devices. -- Stephane -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: feature request: btrfs-image without zeroing data
2011/7/11 Stephane Chazelas stephane_chaze...@yahoo.fr: 2011-07-11 02:00:51 +0200, krz...@gmail.com : Documentation says that btrfs-image zeros data. Feature request is for disabling this. btrfs-image could be used to copy filesystem to another drive (for example with snapshots, when copying it file by file would take much longer time or acctualy was not possible (snapshots)). btrfs-image in turn could be used to actualy shrink loop devices/sparse file containing btrfs - by copying filesystem to new loop device/sparse file. Also it would be nice if copying filesystem could occour without intermediate dump to a file... [...] I second that. See also http://thread.gmane.org/gmane.comp.file-systems.btrfs/9675/focus=9820 for a way to transfer btrfs fs. (Add a layer of copy-on-write on the original devices (LVM snapshots, nbd/qemu-nbd cow...), btrfs add the new device(s) and then btrfs del of the cow'ed original devices. -- Stephane Copying on block level (dd, lvm) is old trick, however this takes same ammount of time regardless of actual space used in filesystem. Hence this feature request. Images inside filesystem can copy only actualy used data and metadata, which dramaticly reduces copy times in large volumes that are not filled up... -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: feature request: btrfs-image without zeroing data
2011-07-11 14:39:18 +0200, krz...@gmail.com : 2011/7/11 Stephane Chazelas stephane_chaze...@yahoo.fr: [...] See also http://thread.gmane.org/gmane.comp.file-systems.btrfs/9675/focus=9820 for a way to transfer btrfs fs. (Add a layer of copy-on-write on the original devices (LVM snapshots, nbd/qemu-nbd cow...), btrfs add the new device(s) and then btrfs del of the cow'ed original devices. [...] Copying on block level (dd, lvm) is old trick, however this takes same ammount of time regardless of actual space used in filesystem. Hence this feature request. Images inside filesystem can copy only actualy used data and metadata, which dramaticly reduces copy times in large volumes that are not filled up... The method I suggest doesn't copy the whole disks, please read more carefully. It can also work to copy from a 3 disk setup to a 1 disk setup or the other way round. With btrfs, you can add devices to a FS dynamically, you can also delete devices in which case data is being transfered to the other devices. The method I suggest uses that feature. Cheers, Stephane -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
feature request: btrfs-image without zeroing data
Documentation says that btrfs-image zeros data. Feature request is for disabling this. btrfs-image could be used to copy filesystem to another drive (for example with snapshots, when copying it file by file would take much longer time or acctualy was not possible (snapshots)). btrfs-image in turn could be used to actualy shrink loop devices/sparse file containing btrfs - by copying filesystem to new loop device/sparse file. Also it would be nice if copying filesystem could occour without intermediate dump to a file... -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
