[linux-audio-dev] Linux kernel HZ, audio latency and how to measure?

[Stephen Sinclair]

> Audio doesn't use setitimer()-driven sleeping.  It's interrupt-driven,
> not timer-driven.

Yes, the driver is interrupt driven, but the driver interrupt handler
is only responsible for getting the data off the card's FIFO and
storing it in memory. (i.e., initialing a DMA transfer.)  It doesn't
do anything with the audio data itself, except pass it on to user
space. Won't HZ make a difference to the user application code which
must wake up to do something with this audio data?  Hence the need for
SCHED_FIFO and the like..


Steve