[LAU] qjackctl fails to exit gracefully on UbuntuStudio 10.4

[fons at kokkinizita.net]

On Tue, Jun 01, 2010 at 12:18:57AM +0200, Robin Gareus wrote:

> On 05/31/2010 10:42 PM, fons at kokkinizita.net wrote:
>
> > If an audio subsystem is using 320MB of memory it's broken. Just dump it.
> > 
> I think you followed Lennart's presentation @LAC2010 [1] explaining the
> motivation for this: Pulseaudio keeps buffers sometimes 10 secs long or
> even more. The reason for that is to have the CPU wake up as little as
> possible in order to save power.

This is a bogus argument.

Keeping software buffers does not help to reduce the number of
times the CPU has to wake up - this depends *only* on how much
the audio *hardware* is able to buffer. For this reason chips 
designed for portable use have something like 2 seconds of
internal buffering.

320 MB corresponds to more than ** 13 minutes ** of stereo signal
in floating point format at 48 kHz.

> FWIW jackd also locks ~80MB in /dev/shm here.

The computer I'm writing this on has just 512 MB. ATM it's 
playing back 32 channels in Ardour, and processing them
with jconvolver. I still have 300 MB free. 


Ciao,

-- 
FA

O tu, che porte, correndo si ?
E guerra e morte !