KDE processor affinity applet?

Can anyone recommend a nice “processor affinity” applet? I’ve been looking around but can’t seem to find anything. Windows Task Manager let’s me right-click and nail MPI threads to specific processors

I only know of the CLI tool taskset.

Using Taskset for Priority Tasks
How to Assign a Process to a Certain CPU Core in Ubuntu Linux

is conky the answer

Thank you, Deano :slight_smile:
I came across the taskset command in the util-linux package. I’m not exactly sure how to use it, but I’m reading up…:nerd: There are so many capabilities at the command line in linux that we KDE folks just don’t know about.

I think OpenMPI may use the taskset command because when invoking mpirun you can tell it to assign threads by-processor or by-CPU

I know conky can monitor stuff - but I don’t think it can pre-assign or reassign threads.

taskset is super simple for it’s basic usage. i just discovered it last night as i had to use it to keep HandBrake from locking up the computer. had to limit it to 4 cpus.


>taskset -c cpu p**rocess


>taskset -pc cpu pid

cpu starts at 0(zero). you can assign a list instead of a single cpu:

>taskset -c 0-3 someprocess

**you can also use strides(every nth cpu):
>taskset -c 0-15:2 someotherprocess (assigns to 0,2,4,6,8,10,12,14)

There is also the whole package (it does it all) with schedtool. I usually symlink it from /usr/sbin/schedtool to /usr/bin/schedtool. Example run handbrake only on cpu 1:

schedtool -a 0 -e ghb

Rather than limiting to cores you are probably better off just using nice to reduce task priority.

I’ve used htop for this. Displays which processor the app/Pid is running on, allows you to set.

Nice/re-nice is an alternative but depends on the situation.

Running a major app on hardware with multiple cores, it can be useful to assign the that app to a particular core so that it can nearly reserve its use for itself. Note that this is a “hard setting” where the app will also be restricted from using any other cores thereby not stepping on other tasks.

Re-nice/nice on the other hand will use the regular scheduler to allocate CPU resources from all cores, and not restricted by any hard settings. There is only a general priority in relation to other running processes.

Note that now systemd provides alternatives to nice/re-nice. I get a headache keeping nice and re-nice info straight (among which direction is higher priority?). And, nice supports only Pids, no names while re-nice supports both. With systemd you only have to declare a non-default priority in the Unit config file.


Thank you for the replies! These look pretty useful. I’ll read up on them, but thanks for the demo code too!

p :slight_smile: