On Fri, Aug 17, 2012 at 12:20 AM, Marc MERLIN <m...@merlins.org> wrote: > On Thu, Aug 16, 2012 at 09:20:00PM -0700, james northrup wrote: >> dunno if this thread is dead, but im inclined to patch in cp --reflink >> to "fdupes" prog. It currently does provide a poor-man's dedupe via >> md5sum and hardlink, or delete. >> >> all the better if the distro-kernels can backport cross-snapshot >> reflinks sooner than later. > > So, I'd love for cp --reflink to bring back a deleted VM (huge file) from a > snapshot back to trunk without duplicating it. > But how would fdupes help? I can't hardlink between two snapshots, can I? > > gandalfthegreat:/mnt/btrfs_pool1# ln > usr_weekly_20120812_00\:02\:01/svn-commit.tmp usr/test > ln: failed to create hard link `usr/test' => > `usr_weekly_20120812_00:02:01/svn-commit.tmp': Invalid cross-device link > > So, is there anything user space can do without kernel support? >
A cross-subvolume copy patch has made it into 3.6_rc http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=362a20c5e27614739c4 This patch will allow cp --reflink across subvolumes, as long as the copy does not cross mount points. -- 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
