On Fri, Oct 4, 2024 at 5:50 PM Gavin McKee via discuss <ovs-discuss@openvswitch.org> wrote: > > Hi, > > We currently experience DNS related timeouts when the ovn controller > is under high load. > > Will this commit ensure that DNS packets needing to be forwarded to an > external resolver will be processed in a timely manner and not lead to > timeouts? > https://github.com/ovn-org/ovn/commit/762ae66cd70efa149d91d35305fcef0040e9addd >
This particular patch is useful when the ovn-controller calls dns_resolve() of ovs/lib/dns_resolve.c [1] to resolve a dns entry. In your case, what are these DNS packets? Are these sent by VMs and ovn-controller pinctrl thread handles these requests and its blocking due to pinctrl_mutex ? If so, I think we need to find a solution for this problem, but the above commit will definitely not help you. Maybe we can maintain a separate mutex to protect the dns_cache [2] so that even if ovn-controller main thread is busy (and not updating the internal dns cache), the DNS packets from the VMs can be handled without any delay in the pinctrl thread. [1] - https://github.com/openvswitch/ovs/blob/main/lib/dns-resolve.c#L148 [2] - https://github.com/ovn-org/ovn/blob/main/controller/pinctrl.c#L3288 Thanks Numan > We currently run OVN 23.09.04. > > Thanks > > Gav > _______________________________________________ > discuss mailing list > disc...@openvswitch.org > https://mail.openvswitch.org/mailman/listinfo/ovs-discuss > _______________________________________________ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
