[ovs-discuss] OVS 2.6.1 hanging with "waiting for <xxx> to quiesce"

[Ben Pfaff]

On Thu, Jan 12, 2017 at 05:01:58PM +0400, Oleg Bondarev wrote:
> Hi,
> 
> During OpenStack testing with OVS 2.6.1 we sometime face an issue that OVS
> may get stuck on a node, looks like:
>  - http://paste.openstack.org/show/594688/
>  - http://paste.openstack.org/show/594509/
>  - http://paste.openstack.org/show/594670/
> 
> Is it some known issue? Was commit [1] supposed to fix it?
> 
> [1]
> https://github.com/openvswitch/ovs/commit/13b6d087906e5284df5e03caa299c11e884a14d4

It's not a known issue.  I don't think that [1] would fix it because
that only affects new threads, whereas this issue is at least sometimes
about the main thread (the first thread created as part of the process)
getting stuck.

The most valuable information for debugging here would be a backtrace of
the stuck thread.  It's blocking for some reason and we don't know why.