Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.
The FDP team is no longer accepting new bugs in Bugzilla. Please report your issues under FDP project in Jira. Thanks.

Bug 1943230

Summary: [FDP 20.1.B.1] openvswitch2.13: Allow PMD auto load balance for limited cross-numa polling
Product: Red Hat Enterprise Linux Fast Datapath Reporter: Timothy Redaelli <tredaelli>
Component: openvswitch2.13Assignee: Kevin Traynor <ktraynor>
Status: CLOSED ERRATA QA Contact: Hekai Wang <hewang>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: FDP 21.BCC: bperkins, ctrautma, fbaudin, fhallal, fiezzi, hewang, jhsiao, kfida, ktraynor, marjones, ralongi, tredaelli
Target Milestone: ---   
Target Release: FDP 21.B   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: openvswitch2.13-2.13.0-79.6.el8fdp Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: 1938162 Environment:
Last Closed: 2021-03-31 15:16:30 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1942590    

Description Timothy Redaelli 2021-03-25 15:52:29 UTC 
+++ This bug was initially created as a clone of Bug #1938162 +++

PMD auto load balance does not trigger a reassignment when
there is any cross-numa polling as an rxq could be polled from a
different numa after reassign so the estimates it makes for improvement after reassignment may be incorrect.

In the case where there is only one numa with pmds available, the
same numa will always poll before and after reassignment, so estimates
are valid and auto load balance could be allowed.

There are customer cases where they are configuring like this and want to use PMD auto load balance. Allow PMD auto load balance to trigger a reassignment in
this case.

--- Additional comment from Kevin Traynor on 2021-03-16 10:59:27 CET ---

v2 patch: https://mail.openvswitch.org/pipermail/ovs-dev/2021-March/381237.html

--- Additional comment from Kevin Traynor on 2021-03-16 16:43:02 CET ---

Some notes for QE validation.

It can be tested with physical NICs or VMs or a combination.

The key things needed for a test are:
- there is at least one interface on a numa node that has no available pmd cores
- there is only one numa with available pmd cores

plus the normal pmd auto load balance conditions
- some core is heavily loaded with multiple rxqs while another one is not
- auto load balance is enabled

With this patch, and the conditions above, auto load balance should occur, where previously it would not be permitted.

--- Additional comment from OvS team on 2021-03-22 21:19:47 CET ---

* Mon Mar 22 2021 Kevin Traynor <ktraynor> - 2.13.0-98
- dpif-netdev: Allow PMD auto load balance with cross-numa. (#1938162)
  [edeaca020b9d40fed8a0a474f35eeec5ed4e338f]
Comment 5 errata-xmlrpc 2021-03-31 15:16:30 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (openvswitch2.13 bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2021:1055