Description of problem: (a) what OSP-10 change is the root cause of the regression: Prior to OVS 2.9 automatic assignment of Rxqs to PMDs (i.e. CPUs) was done by assigning Rxqs in an ascending port/queue order, round robined across the available PMDs. That was changed in OVS 2.9 to order the Rxqs by the measured processing cycles for each, in order to try and keep the busiest Rxqs on different PMDs. For the most part the new scheme should be better, but there could be situations where a user prefers a port/queue scheme because Rxqs from a single port are more likely to be spread across multiple cores, and/or traffic is very bursty/unpredictable. Add the option to have a port/queue based assignment. (b) when was that change introduced: In OVS2.9 (c) the impact of that regression on customers: Possible performance degradation from OVS2.6 to OVS2.9 Related OVS BZ https://bugzilla.redhat.com/show_bug.cgi?id=1616001
Link to upstream patch: https://patchwork.ozlabs.org/patch/964332/ Will it be possible to get the backport to 2.9? Any ETA? Thanks!
(In reply to Daniel Alvarez Sanchez from comment #1) > Link to upstream patch: https://patchwork.ozlabs.org/patch/964332/ > Will it be possible to get the backport to 2.9? Any ETA? > Thanks! Yes, I will make backports for 2.9 (and 2.10) and run through our CI. If no issues, then expect by EOD tomorrow.
++ Thanks a lot Kevin for your swift response. Great job!
The option to have a simple round robin assignment is backported to OVS 2.9 in 'openvswitch-2.9.0-56.el7fdp.1'. Please note the '.1'. It is available in brew here: https://brewweb.engineering.redhat.com/brew/buildinfo?buildID=770069 The option is default *off* and can be enabled with: ovs-vsctl set Open_vSwitch . other_config:pmd-rxq-assign=roundrobin
I guess we need a separate bugzilla then to enable this option? Either from neutron or from OSPD?