[linux-audio-user] Squeezing any more performance out of this old laptop...

[Lee Revell]

On 3/20/07, Spencer Russell <spencer.f.russell at gmail.com> wrote:
> Jackd doesn't complain about not being able to get realtime, so I
> think that's working. Also, when I use chrt to look at the priorities
> of the jackd threads, there are 2 of them running SCHED_FIFO with
> priorities of 20 and 10.
>
> /proc/interrupts tells me that VIA686A (my onboard chipset) is the
> only thing on IRQ10, and chrt tells me that IRQ10 is running
> SCHED_FIFO at priority 50, as are all the other IRQ threads. Boosting
> the priority to 60 doesn't seem to make a difference.

You need JACK and the audio interrupt to be at a higher priority than
all the other IRQ threads.  Try passing -P80 to JACK and set the IRQ
10 thread to priority 60.

Also with limited RAM and any released JACK version it's important to
reduce the stack rlimit to something like 256KB (it defaults to 8MB)
via limits.conf.  Otherwise you lock down a lot of memory that will
never be used.

Lee