cgroup
1、查看进程或者线程cgroup
cat /proc/$process_pid/task/$thread_pid/cgroup
2、查看系统cgroup 整体配置
cat /etc/cgroup.conf
3、把进程添加到某cgroup
echo 1734 > /sys/fs/cgroup/cpuset/TestCgroup/tasks
4、查看cgroup 版本
//查看 cgroup 版本如果包含有cgroup2 的就是安装了的 grep cgroup /proc/filesystems nodev cgroup nodev cgroup2
5、cgroup 中有哪些文件
[root@localhost ~]# ls -lah /sys/fs/cgroup/ total 0 drwxr-xr-x 13 root root 340 Dec 7 16:01 . drwxr-xr-x 8 root root 0 Dec 7 16:01 .. drwxr-xr-x 5 root root 0 Dec 7 16:01 blkio lrwxrwxrwx 1 root root 11 Dec 7 16:01 cpu -> cpu,cpuacct lrwxrwxrwx 1 root root 11 Dec 7 16:01 cpuacct -> cpu,cpuacct drwxr-xr-x 5 root root 0 Dec 7 16:01 cpu,cpuacct drwxr-xr-x 2 root root 0 Dec 7 16:01 cpuset drwxr-xr-x 5 root root 0 Dec 7 16:01 devices drwxr-xr-x 2 root root 0 Dec 7 16:01 freezer drwxr-xr-x 2 root root 0 Dec 7 16:01 hugetlb drwxr-xr-x 5 root root 0 Dec 7 16:01 memory lrwxrwxrwx 1 root root 16 Dec 7 16:01 net_cls -> net_cls,net_prio drwxr-xr-x 2 root root 0 Dec 7 16:01 net_cls,net_prio lrwxrwxrwx 1 root root 16 Dec 7 16:01 net_prio -> net_cls,net_prio drwxr-xr-x 2 root root 0 Dec 7 16:01 perf_event drwxr-xr-x 5 root root 0 Dec 7 16:01 pids drwxr-xr-x 5 root root 0 Dec 7 16:01 systemd
6、cpu,cpuacct
6.1 V1 的cpu,cpuacct
[root@localhost ~]# ls -lah /sys/fs/cgroup/cpu/ total 0 drwxr-xr-x 5 root root 0 Dec 7 16:01 . drwxr-xr-x 13 root root 340 Dec 7 16:01 .. -rw-r--r-- 1 root root 0 Dec 7 16:01 cgroup.clone_children --w--w--w- 1 root root 0 Dec 7 16:01 cgroup.event_control -rw-r--r-- 1 root root 0 Dec 7 16:01 cgroup.procs -r--r--r-- 1 root root 0 Dec 7 16:01 cgroup.sane_behavior -r--r--r-- 1 root root 0 Dec 7 16:01 cpuacct.stat -rw-r--r-- 1 root root 0 Dec 7 16:01 cpuacct.usage -r--r--r-- 1 root root 0 Dec 7 16:01 cpuacct.usage_percpu -rw-r--r-- 1 root root 0 Dec 7 16:01 cpu.cfs_period_us -rw-r--r-- 1 root root 0 Dec 7 16:01 cpu.cfs_quota_us -rw-r--r-- 1 root root 0 Dec 7 16:01 cpu.shares -r--r--r-- 1 root root 0 Dec 7 16:01 cpu.stat drwxr-xr-x 2 root root 0 Dec 7 16:02 machine.slice -rw-r--r-- 1 root root 0 Dec 7 16:01 notify_on_release -rw-r--r-- 1 root root 0 Dec 7 16:01 release_agent drwxr-xr-x 97 root root 0 Dec 7 16:03 system.slice -rw-r--r-- 1 root root 0 Dec 7 16:01 tasks drwxr-xr-x 2 root root 0 Dec 7 16:02 user.slice
6.2 V2 的cpu,cpuacct
bash-4.4# ls /sys/fs/cgroup/cpu,cpuacct/ -lah total 0 dr-xr-xr-x 3 root root 0 Jan 1 1970 . dr-xr-xr-x 12 root root 240 Jan 1 1970 .. drwxrwxrwx 10 root root 0 Jan 1 1970 0 -rw-r--r-- 1 root root 0 Dec 7 16:03 cgroup.clone_children -rw-r--r-- 1 root root 0 Dec 7 16:03 cgroup.procs -r--r--r-- 1 root root 0 Dec 7 16:03 cgroup.sane_behavior -rw-r--r-- 1 root root 0 Dec 7 16:03 cpu.shares -r--r--r-- 1 root root 0 Dec 7 16:03 cpuacct.stat -rw-r--r-- 1 root root 0 Dec 7 16:03 cpuacct.usage -r--r--r-- 1 root root 0 Dec 7 16:03 cpuacct.usage_all -r--r--r-- 1 root root 0 Dec 7 16:03 cpuacct.usage_percpu -r--r--r-- 1 root root 0 Dec 7 16:03 cpuacct.usage_percpu_sys -r--r--r-- 1 root root 0 Dec 7 16:03 cpuacct.usage_percpu_user -r--r--r-- 1 root root 0 Dec 7 16:03 cpuacct.usage_sys -r--r--r-- 1 root root 0 Dec 7 16:03 cpuacct.usage_user -rw-r--r-- 1 root root 0 Dec 7 16:03 notify_on_release -rw-r--r-- 1 root root 0 Dec 7 16:03 release_agent -rw-r--r-- 1 root root 0 Dec 7 16:03 tasks
6.3 cgroup v1 和v2 区别
The cgroupfs files described in this section are only applicable to cgroup v1. For cgroup v2, see Documentation/admin-guide/cgroup-v2.rst. cpu.cfs_quota_us: run-time replenished within a period (in microseconds) cpu.cfs_period_us: the length of a period (in microseconds) cpu.stat: exports throttling statistics [explained further below] cpu.cfs_burst_us: the maximum accumulated run-time (in microseconds)
7、修改cgroup 的核配置
echo 0,2-7 > /sys/fs/cgroup/cpuset/ControlPlane/cpuset.cpus
参考：
https://docs.kernel.org/scheduler/sched-bwc.html
https://www.man7.org/linux/man-pages/man7/cgroups.7.html
http://arthurchiao.art/blog/cgroupv2-zh/
