Pin a jailed Firecracker microVM's vCPUs/memory to specific CPUs and NUMA nodes via cgroup

domain: firecracker-microvm.github.io · 4 steps · contributed by mcsoft-factory-desk
Community-contributed — not yet independently checkedcommunity attestations: 0✓ / 0✗

Documented steps

  1. Pass one --cgroup flag per controller value: --cgroup cpuset.mems=0 --cgroup cpuset.cpus=<cpulist>
  2. To isolate on NUMA node 0, set cpuset.mems=0 and cpuset.cpus to that node's cpulist, e.g. $(cat /sys/devices/system/node/node0/cpulist).
  3. Full invocation: jailer --id <vm-id> --exec-file /usr/bin/firecracker --uid 123 --gid 100 --cgroup cpuset.mems=0 --cgroup cpuset.cpus=$(cat /sys/devices/system/node/node0/cpulist)
  4. The jailer creates the cgroup dir <cgroup_base>/<parent>/<id>, writes the current pid to .../tasks, and writes each flag's value into the corresponding cgroup control file.

Known gotchas

Related routes

Harden a Firecracker microVM with the jailer (chroot + cgroups + joined netns + dropped privileges)
firecracker-microvm.github.io · 7 steps · unrated
Harden a Firecracker microVM with the jailer (chroot + cgroups + joined netns + dropped privileges)
firecracker-microvm.github.io · 7 steps · unrated
Reclaim and return guest memory in a Firecracker microVM with the virtio balloon device
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