Re: [fluid-dev] Figured out cause of excessive CPU usage

[Peter Hanappe]

Josh Green wrote:

> I switched the order
> around in which the different data formats are tried (signed 16 bit
> being the first option) and the CPU usage problem went away :)

I applied that change to the latest version (version 1.0.1, now on
the web site and in CVS).

> Concerning the problem with more underruns ocurring.. On my laptop, X is
> running at a nice level of -10 (higher priority). For some reason even
> when running FluidSynth as root, X gets a higher priority. I reniced the
> Swami FluidSynth thread to -15 and the underrun problem improves
> drastically. It seems like the audio thread is not running SCHED_FIFO,
> although I couldn't determine from the code anything obvious. Cheers.

The audio thread normally uses SCHED_FIFO when permitted. I don't
now exactly how the sheduling parameters map to the nice values.
I'll need to check that next time I'm working on FluidSynth.

Cheers!
Peter

>         Josh Green