ovn-org / ovn-kubernetes / 9678522629

53%

master: 53%

Build Type

Pull #4470

github

Committed by zeeke

Commit Message

ovspinning: Set affinity of each thread

OVS CPU pinning ensures the CPU consumed by the processes `ovsdb-server`
and `ovs-vswitchd` are the same as the OVNkube container. `ovs-vswitchd` process
has threads and calling `SchedSetaffinity()` on the main PID only is does not
guarantee that the already spawned threads inherit that affinity. The following
is an example of such a situation:

```
sh-4.4# taskset -apc $(pgrep ovs-vswitchd)
pid 4059's current affinity list: 0-2,6,9,15-66,69,70,73,79-127
pid 4335's current affinity list: 0-2,32,33,64-66,96,97
pid 2715051's current affinity list: 0-2,5,6,15-66,69,70,73,79-127
pid 2715052's current affinity list: 0-2,5,6,15-66,69,70,73,79-127
pid 2715053's current affinity list: 0-2,5,6,15-66,69,70,73,79-127
...
```

This changes makes the CPU align routine loop over all the threads of the given PID
and invoke `SchedSetaffinity` on all of them.

To test these changes, a simple `sleep 10` process is not enough, as it doesn't spawn
any thread. A go version of the sleep is therefore provided for testing purpose, in the
form of a simple `main`.

Signed-off-by: Andrea Panattoni <apanatto@redhat.com>

Pull Request Pull Request #4470: ovspinning: Set affinity of each thread

Run Details

14 of 23 new or added lines in 1 file covered. (60.87%)

11 existing lines in 3 files now uncovered.

28807 of 54628 relevant lines covered (52.73%)

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