Feature request: (cpu) priority

[yawn]

Motivation

Heavy tests can sometimes have a massive impact on the host they are running on e.g. when they contain CPU intensive integration tasks. Currently there is no fine-grained way of contraining resource usage beyond concurrency limits.

Proposal

While CPU priority can generally be set on (some) OS using e.g. nice it would be neat to be able constrain that on the level of a nextest config file.

Alternatives

nice on a task manager around nextest.

Additional context

This could be interesting also for memory limits etc. but those (maybe?) goes beyond the scope of nextest.

[sunshowers]

Thanks for the feature request. This is a fairly large and substantial feature with a lot of tricky corner cases, so before adding it to nextest I wanted to ask whether you've seen measurable benefits from it. You can try it out with a wrapper script if you like.

[yawn]

OMG I'm blind - I think wrapper scripts are the stopgap I was looking for but apparently did not see. Thank you for the pointer!

Let me regardless elaborate about the error case I see often in our codebase (orchestrated through nextest). The context here are financial simulations.

• Blowing through the memory budget cause oversubscription, swapping and eventually OOM
• Blowing through the thermal budget of CPUs (when fuzzing) on notebooks
• Being not nice when running CPU heavy jobs

It would be a pretty cool feature to have natively in nextest but wrapper scripts will do the job nicely. And for a single user being platform agnostic is not really relevant here.

[sunshowers]

Thanks. Definitely understand the problems here -- I'm curious what measurable benefits you can get out of things. Memory pressure in particular is quite hard to model, I think.