The cgroup-tools from birt

cgroup-tools's Introduction

cgroup-tools

A set of tools to work with cgroup tree and processes classification/QoS, according to it.

More (of a bit outdated) info can be found here.

Main script there - cgconf - allows to use YAML like this to configure initial cgroup hierarcy:

path: /sys/fs/cgroup

defaults:
  _tasks: root:wheel:664
  _admin: root:wheel:644
  freezer:

groups:

  # base:
  #   _default: true # to put all pids here initially
  #   cpu.shares: 1000
  #   blkio.weight: 1000

  user.slice:
    cpu:
      cfs_quota_us: 1_500_000
      cfs_period_us: 1_000_000

  tagged:
    cave:
      _tasks: root:paludisbuild
      _admin: root:paludisbuild
      cpu:
        shares: 100
        cfs_quota_us: 100_000
        cfs_period_us: 250_000
      blkio.weight: 100
      memory.soft_limit_in_bytes: 2G
    desktop:
      roam:
        _tasks: root:users
        cpu.shares: 300
        blkio.weight: 300
        # memory.soft_limit_in_bytes: 2G
      java:
        _tasks: root:users
        cpu.shares: 100
        blkio.weight: 100
        memory.soft_limit_in_bytes: 1G

(from laptop with dying fan, hence cpu bandwidth limits)

And then something like cgrc <tagged-name> <cmd> <args...> to run anything put inside these.

Other tools allow waiting for one cgroup threads to finish before proceeding and put stuff running there on hold easily.

cgconf and cgrc turn out to be surprisingly still useful despite systemd adding knobs to control cgroup resource limits (but not all of them, and spread over lot of small files, which are pain if you need a big picture of e.g. weights) and systemd-run, which hides i/o of whatever it runs in systemd slices.