User:Kim/Special Issue 27/Timekeeping device: Difference between revisions

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  reboot  system boot  6.6.47+rpt-rpi-v Tue May  6 09:24  still running
  reboot  system boot  6.6.47+rpt-rpi-v Tue May  6 09:24  still running
  wtmp begins Wed Apr 23 09:46:29 2025
  wtmp begins Wed Apr 23 09:46:29 2025
-------------------------------------------------------------------------------
===load average (busyness) [https://linux.m2osw.com/load_average]===
$ cat /proc/loadavg
will output
0.11 0.09 0.02 2/192 15046
This means: the first 3 entries are the load average we've seen with uptime and top.
Then comes 2/192 which means 2 processes will run in the next switches and 192 processes are instantiated (most are sleeping.)
Then, the last number, 15046, is the process identifier (pid) of the process that will run next.

Revision as of 21:23, 19 May 2025

tests

can be found on cerealbox timekeeping-device/

terminal

ping
to graph (graphic) visualizing length of seconds
traceroute
time (cmd)

ideas

references

cereal time

general time data

$ timedatectl

outputs

Local time: Mon 2025-05-19 19:13:43 BST
Universal time: Mon 2025-05-19 18:13:43 UTC
RTC time: n/a
Time zone: Europe/London (BST, +0100)
System clock synchronized: yes
NTP service: active
RTC in local TZ: no

running processes

$ ps (or $ ps aux)

outputs information on run processes (aux is more specific, shows user associated with each process, the start time, the memory consumption, the total running time, command associated with each process)
how many processes are running right now?

$ ps aux | wc -l

outputs a number (179). for a nicely formatted output do:

$ echo "User $USER has a total of $(ps -e | wc -l) processes running on $HOSTNAME."

to see realtime running processes and tasks do

$ htop (or $ top)

last reboot

$ last reboot

outputs

reboot   system boot  6.6.47+rpt-rpi-v Tue May  6 09:24   still running
wtmp begins Wed Apr 23 09:46:29 2025

load average (busyness) [1]

$ cat /proc/loadavg

will output

0.11 0.09 0.02 2/192 15046

This means: the first 3 entries are the load average we've seen with uptime and top. Then comes 2/192 which means 2 processes will run in the next switches and 192 processes are instantiated (most are sleeping.) Then, the last number, 15046, is the process identifier (pid) of the process that will run next.