ksmtuned running at 100%

[Ken Sharp]

I have seen this a number of times on my servers and it's a real pain.

For reasons unknown, ksmtuned starts running at 100% CPU. I cannot fathom what would cause this as it appears to be nothing more than a Bash script. My guess is that there's an infinite loop reached somewhere, possibly a race condition.

Last line in the log shows nothing suspicious:

Sat Feb 2 14:57:08 GMT 2019: 788230 > 3941152, start ksm
Sat Feb 2 14:57:08 GMT 2019: 184148 < 788230, boost
Sat Feb 2 14:57:08 GMT 2019: KSMCTL start 1250 425

...but that does mean it hasn't done anything useful in over a month.

The script calls some external apps, such as awk, but it appears to be the script itself that has the issue, i.e. none of the external programs are running when it hits 100%.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ksmtuned 4.20150325build1
ProcVersionSignature: Ubuntu 4.18.0-15.16~18.04.1-generic 4.18.20
Uname: Linux 4.18.0-15-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.6
Architecture: amd64
Date: Thu Apr 11 23:08:21 2019
Dependencies:
 gcc-8-base 8.2.0-1ubuntu2~18.04
 libc6 2.27-3ubuntu1
 libgcc1 1:8.2.0-1ubuntu2~18.04
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ksmtuned
UpgradeStatus: No upgrade log present (probably fresh install)

[roland aus köln (devzero-c)]

it's been a while since this report, does this problem still exist ?

[Ken Sharp (kennybobs)]

I've not seen this since updating to Jammy. I haven't tested any other releases.