get_core_ids() missing cores specfied by isolcpus= on linux boot

[ajvok]

I prevent core 3 (I have 4 cores numbered: 0..3) from being used by anything else on the system by adding isolcpus=3 to my kernel command line parameters.
On reboot this is OK. 'top' shows all 4 cores, with core 3 100% idle. This is as hoped for.

Next I want to run my rust program on core 3 only.
core_affinity::get_core_ids() only returns 3 elements, not 4.
The missing element is for core 3 so I can't then
core_affinity::set_for_current().

This makes it impossible to do what I wanted (run my rust app on its own isolated core).

Does this point to an issue with core_affinity::get_core_ids()? I expected it to return 4 elements.

Thanks for your help. Cheers.

[ajvok]

A bit more effort and I see that a CoreId is simply a...
pub struct CoreId {
id: usize,
}
So I can achieve want with this:
core_affinity::set_for_current(core_affinity::CoreId{id:3});

Thanks for your crate. It works for me now. Maybe it could be improved by core_affinity::get_core_ids() returning all the cores irrespective of the any isolcpus setting?

[raphaelcohn]

I'm no longer maintaining this crate. A far more comprehensive, Linux aware crate for cores, hyperthreads and NUMA nodes is https://github.com/lemonrock/linux-support .