【cpuidle】计算每个cpu进入idle的时间

最新推荐文章于 2025-09-01 14:30:15 发布

原创

最新推荐文章于 2025-09-01 14:30:15 发布 · 3.8k 阅读

1 ·

CC 4.0 BY-SA版权

本文探讨如何通过内核文档来计算每个CPU进入idle状态所花费的时间，详细解析了idle阶段时间的显示以及如何获取前后两次idle状态的时间差，以此来理解CPU在idle状态的行为。

参考内核文档

		Supporting multiple CPU idle levels in kernel

				cpuidle sysfs

System global cpuidle related information and tunables are under
/sys/devices/system/cpu/cpuidle

The current interfaces in this directory has self-explanatory names:
* current_driver
* current_governor_ro

With cpuidle_sysfs_switch boot option (meant for developer testing)
following objects are visible instead.
* current_driver
* available_governors
* current_governor
In this case users can switch the governor at run time by writing
to current_governor.


Per logical CPU specific cpuidle information are under
/sys/devices/system/cpu/cpuX/cpuidle
for each online cpu X

--------------------------------------------------------------------------------
# ls -lR /sys/devices/system/cpu/cpu0/cpuidle/
/sys/devices/system/cpu/cpu0/cpuidle/:
total 0
drwxr-xr-x 2 root root 0 Feb  8 10:42 state0
drwxr-xr-x 2 root root 0 Feb  8 10:42 state1
drwxr-xr-x 2 root root 0 Feb  8 10