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

[Josh Green]

Looks like I found what the problem is on my laptop and the new
FluidSynth ALSA driver. Its using floating point data to access the
sound card. When I look at the hw_params in the /proc/asound file system
though, its actually in 16 bit integer mode, so I think there is some
sort of bad translation going on in ALSA lib. 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 :)

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.
        Josh Green