mirror of
https://github.com/kata-containers/kata-containers.git
synced 2026-04-29 20:34:53 +00:00
48669a894e
Port the Go runtime's enable_vcpus_pinning feature to runtime-rs. The Go runtime already lets users pin each vCPU thread to a specific host CPU when the vCPU count matches the sandbox cpuset size, using sched_setaffinity. This is useful for latency-sensitive workloads that benefit from eliminating cross-CPU migration of vCPU threads. The approach mirrors the Go implementation: After VM start and on every container add/update/delete, we fetch the vCPU thread IDs (via QMP query-cpus-fast for QEMU), compute the union of all containers' OCI cpusets, and if the two counts match, pin vCPU i to cpuset[i]. If they diverge (hotplug, container removal, etc.) we reset all threads back to the full cpuset so nothing gets stuck on a single core. The pinning check lives in CgroupsResourceInner::update_sandbox_cgroups, which already runs at exactly the right points in the lifecycle. The enable_vcpus_pinning flag flows from the TOML config through CgroupConfig into the cgroup resource layer, and can also be overridden per-pod via the io.katacontainers.config.runtime.enable_vcpus_pinning annotation. The QEMU config templates default to false. The NV GPU configs will get their own default (true) in a follow-up once those templates are added. Signed-off-by: Fabiano Fidêncio <ffidencio@nvidia.com> Made-with: Cursor