sysfs

• /sysfs/class/net

• /proc/sysrq-trigger

• /sys/block/mmcblk0/mmcblk0p2/ro

• /proc/pressure - PSI - Pressure Stall Information - v4.20 - Facebook 2018

  • io
  • cpu
  • memory

• /sys/fs/cgroup/cg1/io.pressure

• CONFIG_PSI=y

• CONFIG_PSI_DEFAULT_DISABLED=y

  • psi=1

cat /boot/config-lts | grep PSI

for_each_possible_cpu(cpu)

nr_active += cpu_of(cpu)->nr_running + cpu_of(cpu)->nr_uninterruptible;

avenrun[n] = avenrun[0] * exp_n + nr_active * (1 - exp_n)

• avg10、avg60、avg300 分别代表 10s、60s、300s 的时间周期内的阻塞时间百分比。total 是总累计时间，以毫秒为单位。
• https://facebookmicrosites.github.io/psi/docs/overview
• https://www.kernel.org/doc/html/latest/accounting/psi.html
• https://lwn.net/Articles/759658/
• https://lwn.net/Articles/759781/

find /sys -type f -name power_now 2>/dev/null
sensors power_meter-acpi-0

/proc/acpi/battery/BAT0/state /sys/bus/acpi/drivers/battery/PNP0C0A:00/power_supply/BAT0/power_now

tlp-stat -b --- TLP 1.1 --------------------------------------------

+++ Battery Status /sys/class/power_supply/BAT1/manufacturer = SANYO /sys/class/power_supply/BAT1/model_name = L12S3F01 /sys/class/power_supply/BAT1/cycle_count = 16 /sys/class/power_supply/BAT1/energy_full_design = 32560 [mWh] /sys/class/power_supply/BAT1/energy_full = 16180 [mWh] /sys/class/power_supply/BAT1/energy_now = 16090 [mWh] /sys/class/power_supply/BAT1/power_now = 0 [mW] /sys/class/power_supply/BAT1/status = Unknown

Charge = 99.4 [%] Capacity = 49.7 [%]

modprobe i2c-dev sensors-detect

/sys/kernel

• /sys/kernel/debug
• /sys/kernel/security
  • securityfs
• /proc/sys/kernel/hotplug
• /sys/kernel/config
• /sys/firmware/efi/efivars
• /sys/fs/pstore
• /etc/init.d/sysfs

modprobe configfs
grep "configfs$" /proc/filesystems
mount -n -t configfs -o nodev,noexec,nosuid configfs /sys/kernel/config

oom

• /proc/self/oom_score
  • oom_score_adj
• /proc/sys/vm/overcommit_memory
  • 2 - 不 overcommit - 不会 kill 而是返回错误
  • vm.oom-kill
  • panic_on_oom