logging load average and memory usage on Linux servers

Just redirecting the output of top to a text file, like top >> logtop, we get lot of unprintable characters due to its refresh nature.

uptime gives load average.

https://linuxconfig.org/how-to-obtain-linux-s-system-load-average-report-since-last-reboot

top can do various things, like batch mode, -b

https://unix.stackexchange.com/questions/352594/add-timestamps-to-top-command-output

Probably more efficient to just log timestamps, free and uptime.

So, put in a cron job to run every 15 minutes,

*/15 * * * * /home/path/to/logtopscript.sh

$ more logtopscript.sh

#!/usr/bin/bash

echo $(date '+%Y-%m-%d:%H:%M:%S') uptime: $(uptime) free: $(free)  >> /home/path/to/toplog.txt

This can be imported into spreadsheets like LibreOffice Calc using <SPACE> as the delimiter, but has problems with uptime's output not being exactly the same length - sometimes

up 1 hour

sometimes

up 6 days,  8:33

etc. It has issues for 3-4 data points every day, which need to be manually finagled. Probably a regex to select only the load average can solve that.