Re: [iiwusynth-devel] Re: [Swami-devel] update and todo list

[Tim Goetze]

Josh Green wrote:

[...]

>Yes, performance seems like the most major issue for me. I am currently
>using a 366mhz PII laptop and I have no trouble in maxing out my CPU. I
>was also just reminded again today that running Swami/iiwusynth as root
>is a bad idea. I connected up my little loop sequencer program via the
>ALSA sequencer and started to crank the tempo up. Computer totally
>frozen, not even SysRq keys would work, still audible noises emitting
>though :)  I'm just glad I'm using ext3 journaling. Are there any better
>ways of getting low latency audio without the perils of SCHED_FIFO?

no, you can't do without SCHED_FIFO. it's the only way of ensuring
your process is capable of processing promptly and frequently. without
it, when the audio interface fires an interrupt and your process
is marked ready to run in kernel, it is just one among a random
number of processes contending for cpu. therefore the time it takes
until your process actually gets to deliver data to (or fetch from) 
the audio interface is not determinate in SCHED_NORMAL.

occasionally i manage to lock up this box in SCHED_FIFO and SysRq
hasn't failed me yet. strange it does this to you. have you checked
it works at all?

tim