Firecracker v0.23.0

Added

• Added full support for AMD CPUs (General Availability). More details here.
• Added snapshot-restore functionality (Developer preview). More details here.
• Added metric for throttled block device events.
• Added metrics for counting rate limiter throttling events.
• Added metric for counting MAC address updates.
• Added metrics for counting TAP read and write errors.
• Added metrics for counting RX and TX partial writes.
• Added metrics that measure the duration of pausing and resuming the microVM,
  from the VMM perspective.
• Added metric for measuring the duration of the last full snapshot created,
  from the VMM perspective.
• Added metric for measuring the duration of loading a snapshot, from the VMM
  perspective.
• Added metrics that measure the duration of pausing and resuming the microVM,
  from the API (user) perspective.
• Added metric for measuring the duration of the last full snapshot created,
  from the API (user) perspective.
• Added metric for measuring the duration of loading a snapshot, from the API
  (user) perspective.
• Added track_dirty_pages field to machine-config. If enabled, Firecracker
  can create incremental guest memory snapshots by saving the dirty guest pages
  in a sparse file.
• Added a new API call, PATCH /vm, for changing the microVM state (to
  Paused or Resumed).
• Added a new API call, PUT /snapshot/create, for creating a full snapshot.
• Added a new API call, PUT /snapshot/load, for loading a snapshot.
• Added new jailer command line argument --cgroup which allow the user to
  specify the cgroups that are going to be set by the Jailer.

Fixed

• Boot time on AMD achieves the desired performance (i.e under 150ms).

Changed

• The logger level field is now case-insensitive.
• Disabled boot timer device after restoring a snapshot.
• Enabled boot timer device only when specifically requested, by using the
  --boot-timer dedicated cmdline parameter.
• firecracker and jailer --version now gets updated on each devtool
  build to the output of git describe --dirty, if the git repo is available.
• MicroVM process is only attached to the cgroups defined by using --cgroups
  or the ones defined indirectly by using --node.