On Thu, 19 Mar 2015 07:18:29 AM Erkki Seppala wrote: > > But as a user level facility, I want to be able to snapshot before > > making a change to a tree full of source code and (re)building it all > > over again. I may want to keep my new build, but I may want to flush > > it and return to known good state. > > You may want to check out cp --reflink=always (different from cp > --link), which creates copy-on-write copy of the data. It isn't quite as > fast as snapshots to create, but it's still plenty fast and without the > downsides of subvolumes.
In which situations is --reflink=always expected to fail on BTRFS? I recently needed to move /home on one system to a subvol (instead of being in the root subvol) and used cp --reflink=always which gave a few errors when running with BTRFS on kernel 3.16.7-ckt7-1. I was in a hurry and didn't try to track down the caue, I just ran it again with --reflink=auto which gave no errors and completed very quickly (obviously the files which couldn't be reflinked were small). -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/ -- 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
