On Fri, Nov 22, 2013 at 03:30:54PM +0800, Chengyuan Li wrote: > I'm testing ovs 2.0, bridged mode, configed miss-handlers with 28-thread > and 4-thread respectively, sending the same pattern (short-live connection) > and same amount traffic to the VM running on this vswitch, 28-thread > configuration consume much more cpu than 4-thread, but the traffic volume > should be far from ovs-vswitchd's max capacity. > > - 28-thread > ovs-vswitchd cpu usage: 2741% > kernel missed packets: 130646/sec > host throughput total pps 139679/sec > > - 4-thread > ovs-vswitchd cpu usage: 510% > kernel missed packets: 130726/sec > host throughput total pps 135715/sec > > The perf shows that 70% cycles are consumed in __ticket_spin_lock() in > 28-thread case. Further perf lock shows that futex_queues lock contention > is very heavy. So it mean that pthread_mutex_lock() in ovs-vswitchd trigger > the high cpu usage of spin_lock in the kernel. > > Is this a known issue of kernel futex or ovs-vswitchd can improve?
ovs-vswitchd can definitely improve and we are in the midst of that work. For now I'd suggest using only a small number of threads. _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss
