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Description of problem:

Few months ago in irqbalance was introduced feature which reads isolated cpu from kernel and don't assign interrupts to them.

Thing is that when you're using IRQBALANCE_BANNED_CPUS it also automatically disables this feature. Personally I think this is strange. Nevertheless I would suggest change this logic (I'm honestly not sure if logic behind this bahaviour is correct or not) or document this behaviour on man page. 


Version-Release number of selected component (if applicable):
irqbalance-1.0.7-8

In the commit ca5a3f13 and 2dddcfef which added autodetect and ban isolated CPUs, the commit message makes it very clear that IRQBALANCE_BANNED_CPUS will override the automatically detected banned_cpus, so it's intended to do so.
I'll update the man page so this will be no longer confusing.

The man page is definitely improved - of course, the understandability is in the eye of the beholder - maybe it would be even clearer to add "If IRQBALANCE_BANNED_CPUS is specified, it will override the default exclusion of isolated and adaptive-tick CPUs." Will open a new bug for that, but even the current state is significantly better.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2019:2179