On 03/28/2013 10:07 AM, Theodore Ts'o wrote: > Any update about whether Gluster can address this without needing the > ioctl patch? Or should we push the ioctl patch into ext4 for the next > merge window? We have two approaches that don't require the ioctl patch: * http://review.gluster.org/#change,4675 This takes the approach of mapping between the underlying filesystems' d_off values and our own, using a cache. It works for obvious cases, but it's a really horrible kludge. * http://review.gluster.org/#change,4711 This is Avati's and Zach's approach, which "rounds off" the ext4 d_off values to free up some bits that we can use. There seems to be a general consensus (among the people who've discussed it on this list) that the approach is preferable, but it doesn't quite work yet. Between those two and the possibility of "tune2fs -O ^dir_index" I think we can keep this from affecting our users, but since they're both a bit unclean in different ways the ioctl might still be desirable. I'll let others who've been more involved with that (e.g. Avati/Zach/Eric) give a more authoritative answer.
