Hi, > I just tested with tap2:aio and that worked (had an old image of the VM on lvm still so just tested with that). Switching back to rbd and it crashes every time, just as postgres is starting in the vm. Booting into single user mode, waiting 30 seconds, then letting the boot continue it still crashes at the same point so I think it's not a timing thing - maybe postgres has a disk access pattern that is triggering the bug? Mmm, that's really interesting. Could you try to disable request merging ? Just give option max_merge_size=0 in the tap2 disk description. Something like 'tap2:tapdisk:rbd:rbd/test:max_merge_size=0,xvda2,w' Cheers, Sylvain -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html