Hello On NetBSD, tests/basic/afr/entry-self-heal.t always fail on this scenario: mkdir spb_heal kill brick brick0 touch spb_heal/0 glusterfs volume start force kill_brick brick1 touch spb_heal/1 glusterfs volume start force At that time, conservative merge takes off and copy spb_heal/0 and spb_heal/1 in each brick where it is missing. That works, but on NetBSD we are left with AFR xattr on spb_heal directory telling each brick accuses the other for metadata. This metadata split brain that will not self heal. This happens because after adding an entry, parent directory (spb_heal here) mtime/ctime must be updated. On Linux, it seems the filesystem is responsible for that. On NetBSD, the kernel filesyste-independant code takes care of it and will send a SETATTR to update ctime/mtime on parent directory. So when we touch spb_heal/0 and spb_heal/1, the NetBSD kernel sends a SETATTR for spb_heal ctime/mtine, and since the other brick is down, here is our metadata split brain. In http://review.gluster.org/9267, Krutika Dhananjay fixes the test by clearing AFR xattr to remove the split brain state, but while it let the test pass, it does not address the real world problem that will leave metadata split brain that does not self heal. Here is a proposal: we know that at the end of conservative merge, we should end up with the situation where directory ctime/mtime is the ctime of the most recently added children. And fortunately, as conservative merge happens, parent directory ctime/mtime are updated on each child addition, and we finish in the desired state. In other words, after conservative merge, parent directory metadata split brain for only ctime/mtime can just be cleared by AFR without any harm. Does it looks reasonable? Any opinion? -- Emmanuel Dreyfus http://hcpnet.free.fr/pubz manu@xxxxxxxxxx _______________________________________________ Gluster-devel mailing list Gluster-devel@xxxxxxxxxxx http://supercolony.gluster.org/mailman/listinfo/gluster-devel
