Hi Guys, It looks like under some circumstances dmeventd doesn't properly release a lock it's holding on /var/lock/lvm/V_${vg} ... I suspect it might be related to snapshots (also see an email from a few hours back). However, dmeventd is trying to do *something* with the lock held, or sleeping, please see below. Firstly, at the time of testing, dmeventd is the only process that has the lock file open: [root@hostjmdb2 proc]# ls -la */fd/* 2>/dev/null | grep -E 'V_vg' lrwx------ 1 root root 64 Feb 21 11:52 5519/fd/1046 -> /var/lock/lvm/V_vg_hostdb02 [root@hostjmdb2 proc]# At this point if I run "lvs" (and then press ^C) I get this: [root@hostname proc]# lvs /dev/vg_hostdb02/snap-lib_mysql-2013-02-20.18: read failed after 0 of 4096 at 536870846464: Input/output error ... bunch of other IO failures on snapshots that has presumably become invalid /dev/vg_hostdb02/snap-lib_mysql-2013-02-21.06: read failed after 0 of 4096 at 4096: Input/output error ^C CTRL-c detected: giving up waiting for lock /var/lock/lvm/V_vg_hostdb02: flock failed: Interrupted system call Can't get lock for vg_hostdb02 Skipping volume group vg_hostdb02 [root@hostname proc]# So the only logical conclusion is that dmeventd has the lock held. And according to wchan in /proc/5519 dmeventd is blocking in poll_schedule_timeout ... so my suspicion is that under some error condition dmeventd doesn't release it's lock on V_ ... perhaps an attempt to extend the snapshot, which then becomes invalid before the extend is issued or something. Specific distro in question is Centos 6.5, and lvm2-2.02.95-10.el6.x86_64 -- Kind Regards, Jaco Kroon _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/