Easily set real-time priority

[supercurio]

Hi vityafx, thanks for this useful crate :)
I'm trying to set the highest real-time highest priority for low-latency audio operation.

let thread_id = thread_native_id();
set_thread_priority(thread_id,
                    ThreadPriority::Max,
                    ThreadSchedulePolicy::Realtime(RealtimeThreadSchedulePolicy::Fifo)).unwrap();

This always fails with: Err value: Pthread(22), whereas this is fine:

set_thread_priority(thread_id,
                    ThreadPriority::Min,
                    ThreadSchedulePolicy::Normal(NormalThreadSchedulePolicy::Normal)

Also this code has the result expected, but it's surprising to have a numeric value.

let policy = ThreadSchedulePolicy::Realtime(RealtimeThreadSchedulePolicy::Fifo);
let params = ScheduleParams { sched_priority: 3 };
set_thread_schedule_policy(thread_id, policy, params).unwrap();

How would you set the highest real-time priority ergonomically?

[iddm]

Thank you for reporting an issue! I am going to look at it as I have time. As of now, I know that the error you have (Pthread(22)) is this:

EINVAL prio is not valid for the scheduling policy of the specified thread.

So, there is something related to priority which I pass to the function. I am going to work on it more but a bit later, just posting this info here for letting you know I got your problem.

[supercurio]

Thanks :)
I also noticed that the priority in the end, as shown by top when listing threads is not as high as another audio C++ program I was looking at (when using set_thread_schedule_policy)

[iddm]

I am sorry, I realized I don't have a time to work on it this week. I already have guesses why this can happen but I have not tested it yet. I'll try doing it in the end of weekend or next week.

[iddm]

Sorry, still have no time. Can't give you any forecast.

[surban]

This is caused by set_thread_priority not setting the scheduling policy as documented. See #5 for a fix.

[iddm]

Thank you guys for participating in this. I have time now and see this has already been fixed. I am closing this, but if you have something to say or to fix in this issue, feel free to mention it.