[libvirt-users] libvirtd hangs

Hello everybody! We have a cluster of servers managed by VMmanager 5 KVM (by ispsystem). A typical node: # cat /etc/redhat-release CentOS Linux release 7.3.1611 (Core) # uname -r 3.10.0-693.11.6.el7.x86_64 # rpm -qa |grep libvirt libvirt-daemon-driver-qemu-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-disk-3.7.0-1.el7.centos.x86_64 libvirt-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-core-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-nodedev-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-lxc-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-iscsi-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-gluster-3.7.0-1.el7.centos.x86_64 libvirt-daemon-kvm-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-network-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-interface-3.7.0-1.el7.centos.x86_64 libvirt-daemon-config-network-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-rbd-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-3.7.0-1.el7.centos.x86_64 libvirt-libs-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-nwfilter-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-secret-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-mpath-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-scsi-3.7.0-1.el7.centos.x86_64 libvirt-client-3.7.0-1.el7.centos.x86_64 libvirt-daemon-3.7.0-1.el7.centos.x86_64 libvirt-daemon-config-nwfilter-3.7.0-1.el7.centos.x86_64 libvirt-daemon-driver-storage-logical-3.7.0-1.el7.centos.x86_64 # rpm -qa |grep qemu qemu-kvm-common-rhev-2.6.0-27.1.el7.centos.maros.x86_64 ipxe-roms-qemu-20160127-5.git6366fa7a.el7.noarch qemu-img-rhev-2.6.0-27.1.el7.centos.maros.x86_64 qemu-kvm-rhev-2.6.0-27.1.el7.centos.maros.x86_64 # rpm -qa |grep ebtables ebtables-2.0.10-15.el7.centos.marosnet.x86_64 ebtables build with patch https://marc.info/?l=netfilter-devel&m=150728694430435 (described at https://bugzilla.redhat.com/show_bug.cgi?id=1495893) Sometimes libvirtd just hangs and stops answering for virsh requests (like `virsh list --all`). At those moments: # strace -p 5786 read(53, "\0\0\0\34", 4) = 4 read(53, "keep\0\0\0\1\0\0\0\2\0\0\0\2\0\0\0\0\0\0\0\0", 24) = 24 poll([{fd=5, events=POLLIN}, {fd=7, events=POLLIN}, {fd=12, events=POLLIN}, {fd=13, events=POLLIN}, {fd=14, events=POLLIN}, {fd=15, events=POLLIN}, {fd=19, events=POLLIN}, {fd=23, events=POLLIN|POLLERR|POLLHUP}, {fd=21, events=POLLIN|POLLERR|POLLHUP}, {fd=27, events=POLLIN|POLLERR|POLLHUP}, {fd=25, events=POLLIN|POLLERR|POLLHUP}, {fd=22, events=POLLIN|POLLERR|POLLHUP}, {fd=24, events=POLLIN|POLLERR|POLLHUP}, {fd=26, events=POLLIN|POLLERR|POLLHUP}, {fd=29, events=POLLIN|POLLERR|POLLHUP}, {fd=30, events=POLLIN|POLLERR|POLLHUP}, {fd=31, events=POLLIN|POLLERR|POLLHUP}, {fd=33, events=POLLIN|POLLERR|POLLHUP}, {fd=32, events=POLLIN|POLLERR|POLLHUP}, {fd=36, events=POLLIN|POLLERR|POLLHUP}, {fd=35, events=POLLIN|POLLERR|POLLHUP}, {fd=39, events=POLLIN|POLLERR|POLLHUP}, {fd=40, events=POLLIN|POLLERR|POLLHUP}, {fd=41, events=POLLIN|POLLERR|POLLHUP}, {fd=44, events=POLLIN|POLLERR|POLLHUP}, {fd=42, events=POLLIN|POLLERR|POLLHUP}, {fd=43, events=POLLIN|POLLERR|POLLHUP}, {fd=48, events=POLLIN|POLLERR|POLLHUP}, {fd=49, events=POLLIN|POLLERR|POLLHUP}, {fd=59, events=POLLIN|POLLERR|POLLHUP}, {fd=46, events=POLLIN|POLLERR|POLLHUP}, {fd=50, events=POLLIN|POLLERR|POLLHUP}, ...], 43, 5000 # gdb -p 5786 (gdb) thread apply all bt Thread 17 (Thread 0x7f411a9d7700 (LWP 5788)): #0 pthread_cond_wait@(a)GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007f4129c2a2e6 in virCondWait (c=c@entry=0x7f412b18ebb8, m=m@entry=0x7f412b18eb90) at util/virthread.c:154 #2 0x00007f4129c2ada3 in virThreadPoolWorker (opaque=opaque@entry=0x7f412b183ab0) at util/virthreadpool.c:124 #3 0x00007f4129c2a078 in virThreadHelper (data=<optimized out>) at util/virthread.c:206 #4 0x00007f4127033dc5 in start_thread (arg=0x7f411a9d7700) at pthread_create.c:308 #5 0x00007f4126d6273d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113 Thread 16 (Thread 0x7f411a1d6700 (LWP 5789)): #0 pthread_cond_wait@(a)GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007f4129c2a2e6 in virCondWait (c=c@entry=0x7f412b18ebb8, m=m@entry=0x7f412b18eb90) at util/virthread.c:154 #2 0x00007f4129c2ada3 in virThreadPoolWorker (opaque=opaque@entry=0x7f412b183a00) at util/virthreadpool.c:124 #3 0x00007f4129c2a078 in virThreadHelper (data=<optimized out>) at util/virthread.c:206 #4 0x00007f4127033dc5 in start_thread (arg=0x7f411a1d6700) at pthread_create.c:308 #5 0x00007f4126d6273d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113 Thread 15 (Thread 0x7f41199d5700 (LWP 5790)): #0 pthread_cond_wait@(a)GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007f4129c2a2e6 in virCondWait (c=c@entry=0x7f412b18ebb8, m=m@entry=0x7f412b18eb90) at util/virthread.c:154 #2 0x00007f4129c2ada3 in virThreadPoolWorker (opaque=opaque@entry=0x7f412b183950) at util/virthreadpool.c:124 #3 0x00007f4129c2a078 in virThreadHelper (data=<optimized out>) at util/virthread.c:206 #4 0x00007f4127033dc5 in start_thread (arg=0x7f41199d5700) at pthread_create.c:308 #5 0x00007f4126d6273d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113 Thread 14 (Thread 0x7f41191d4700 (LWP 5791)): #0 pthread_cond_wait@(a)GLIBC_2.3.2 () at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185 #1 0x00007f4129c2a2e6 in virCondWait (c=c@entry=0x7f412b18ebb8, m=m@entry=0x7f412b18eb90) at util/virthread.c:154 #2 0x00007f4129c2ada3 in virThreadPoolWorker (opaque=opaque@entry=0x7f412b1838a0) at util/virthreadpool.c:124 #3 0x00007f4129c2a078 in virThreadHelper (data=<optimized out>) at util/virthread.c:206 #4 0x00007f4127033dc5 in start_thread (arg=0x7f41191d4700) at pthread_create.c:308 #5 0x00007f4126d6273d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113 Thread 13 (Thread 0x7f41189d3700 (LWP 5792)): ---Type <return> to continue, or q <return> to quit--- log_level = 3 at /etc/libvirt/libvirtd.conf doesn't help to detect the problem. Actually, libvirtd continues acting, but is not responding. It's like waiting for something... may be an answer. No zombieing, no cpu loading. This fixes the issue: rm -f /run/ebtables.lock ; killall -9 virsh; systemctl restart systemd-{journald,udevd,logind,machined} ; systemctl restart libvirtd The same situation appears with libvirt-3.2.0-14.el7_4.7.x86_64. Could anybody help to resolve this situation?