1

I am a software developer and I come into contact with a lot of unstable software. Recently I made a small game, which for some reason memleaks until the system hangs and is unresponsive. Usually, REISUB helps, but sometimes not even that and you need to do a hard poweroff.

Then it happened to me again with another program, so I thought to myself that this could easily be prevented by writing a script that monitors mem usage and if it crosses a certain value per PID over a certain amount of time, it gets a SIGKILL to take it down immediately.

Any ideas? Thanks

Improve this question
3
  • 1
    Why not limit usage in the first place? Commented Jan 28, 2021 at 13:03
  • @FelixJN how would I go about that? Commented Jul 13, 2021 at 17:45
  • 1
    One way via prlimit, i.e. setting a limit for a single process from the OS side. The other option depends on the programming language you use: set a memory limit in the code itself. Commented Jul 14, 2021 at 6:28

2 Answers 2

Reset to default
1

Please install earlyoom and enable or any of its alternatives which are listed here:

https://github.com/hakavlad/nohang

earlyoom is now used by default by Fedora.

The Linux kernel OOM handling is quite horrible and more often than not doesn't work without user space utilities/helpers.

You can also use man limits.conf and cgroups to limit your application RAM use.

Improve this answer
3
  • Thank you for your response, but I asked about writing it, not just downloading someone else's software. Commented Jan 29, 2021 at 14:02
  • 1
    There are already readily available tested solutions which solve your issue - I'm not sure why you need to code something. Commented Jan 29, 2021 at 15:28
  • 1
    Possible alternatives: github.com/facebookincubator/oomd "oomd leverages PSI and cgroupv2 to monitor a system holistically. oomd then takes corrective action in userspace before an OOM occurs in kernel space." or also launch your program using systemd-run --user --no-block --scope -p MemoryHigh=1G $CMD Commented Feb 1, 2021 at 15:07
0

Simple idea: check if memory exceeds a given value, and check again after some time. Hand out strikes, three strikes in a row will lead to a kill. Need to know: PID of process

#!/bin/bash
pid=$1
strike=0

#as long as process exists
while (kill -0 $pid 2>/dev/null) ; do
  #get RAM usage in kB
  ram=$(pmap -x $pid | tail -1 | awk '{print $3}')
  #compare to threshold, 1,000,000kB
  if [[ 1000000 -lt $ram ]] ; then
    strike=$((strike+1))
    if [[ strike -eq 3 ]] ; then
       kill $pid
       exit
    fi
  else
    strike=0
  fi
  sleep 5
done
Improve this answer

You must log in to answer this question.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.