[ovs-dev] 100% CPU in ovs-vswitchd (again)

[Alex Wang]

Found the issue, I have idea of unit testing it, will experiment on it,

On Tue, Sep 30, 2014 at 11:11 AM, Ben Pfaff <blp at nicira.com> wrote:

> It's not the first time we've had this kind of bug.  Last time, I
> tried to think of a good unit test, but did not succeed.
>
> On Tue, Sep 30, 2014 at 10:32:15AM -0700, Alex Wang wrote:
> > I can reproduce it, working on a fix,
> >
> > Thx for reporting~
> >
> > On Tue, Sep 30, 2014 at 9:37 AM, Ben Pfaff <blp at nicira.com> wrote:
> >
> > > There's still a 100% CPU bug in ovs-vswitchd.  Run "make sandbox", then
> > > run a second ovs-vswitchd inside the subshell (just run a bare
> > > "ovs-vswitchd" without any parameters).  You get output like this:
> > >
> > >     2014-09-30T16:33:45Z|00001|ovs_numa|INFO|Discovered 8 CPU cores on
> > > NUMA node 0
> > >     2014-09-30T16:33:45Z|00002|ovs_numa|INFO|Discovered 1 NUMA nodes
> and 8
> > > CPU cores
> > >
> > >
> 2014-09-30T16:33:45Z|00003|reconnect|INFO|unix:/home/blp/nicira/ovs/tutorial/sandbox/db.sock:
> > > connecting...
> > >
> > >
> 2014-09-30T16:33:45Z|00004|reconnect|INFO|unix:/home/blp/nicira/ovs/tutorial/sandbox/db.sock:
> > > connected
> > >     2014-09-30T16:33:45Z|00005|bridge|ERR|another ovs-vswitchd process
> is
> > > running, disabling this process (pid 13812) until it goes away
> > >     2014-09-30T16:33:48Z|00006|poll_loop|INFO|wakeup due to 1-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00007|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00008|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00009|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00010|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00011|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00012|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00013|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00014|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >     2014-09-30T16:33:48Z|00015|poll_loop|INFO|wakeup due to 0-ms
> timeout
> > > at ../vswitchd/bridge.c:2723 (100% CPU usage)
> > >
> > > The cited line in bridge.c is:
> > >
> > >         seq_wait(connectivity_seq_get(), connectivity_seqno);
> > >
> > > Thanks,
> > >
> > > Ben.
> > >
>