On Tue, Apr 23, 2013 at 01:56:17AM +0000, pengyi Peng(Yi) wrote: > I find that when ovs-vswitchd memory is abnormally growing, backlog > in struct rpc is growing fast too. Almost every time in jsonrpc_run, > stream_send returns -EAGAIN, the msg holds and waits next time to > send. The backlog pluses the strlen of next msg. So the backlog can > be as big as 1228252. But after all ports are deleted, the backlog > will slowly decrease and in the end be zero again. However, at this > time, with top command, the memory of ovs-vswitchd doesn't change at > all. It is still bigger than the memory before all interfaces are > deleted.
None of the above is unexpected. In particular, it is normal for Unixs implementation of malloc() to hold on to allocated memory even after it has been freed. > And last night, I tested another situation. > First I create 200 ports which try to connect to interfaces that don't exist. > (ovs-vsctl --timeout=5 --no-wait add-port br-0 tap-no-exist$i > vlan_mode=access tag=0 -- set interface tap-no-exist$i type=system) > > Second, I create 1000 ports connected to interfaces that exist. > ( tunctl -t vif$i > ifconfig vif$i up > ovs-vsctl --timeout=5 --no-wait add-port br-0 vif$i vlan_mode=access tag=0 -- > set interface vif$i type=system) > > After all ports finish connecting to interfaces, the memory of > ovs-vswitchd is 530832KB. Today it changes to 524444KB. But the > backlog in struct rpc is still very big(455532592). It is unusual to see the backlog grow so high. We haven't observed that behavior before when we've created and destroyed many interfaces, or at least this is the first time it's been reported to me. Can you figure out why ovs-vswitchd is trying to commit so many transactions? It would be better for it to do avoid doing that. Maybe we can do something to coalesce transactions or to skip some of them. _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss
