[pulseaudio-discuss] Best Case Latency

[Patrick Shirkey]

On Sat, September 28, 2013 3:12 am, Patrick Shirkey wrote:
>
>> On Sat, September 28, 2013 12:53 am, Tanu Kaskinen wrote:
>> I don't remember if the alsa compatibility layer forwards the
>> stream under/overrun notifications to the alsa application - IIRC there
>> were problems when those were reported and there were different
>> problems
>> when those were not reported, and I don't remember what the current
>> code
>> does.
>>

This seems like it would be a good place to verify. Do you have any
suggestions for how to test/measure the code/buffer at this point in the
graph?

Also does anyone know why the PA Stream Buffer is hovering around 10ms?
That number doesn't appear to match the 64 frames/period that JACK is set
to so it would be useful to verify that it is calculated correctly and/or
if it can be lowered.


>
> This is with a newer version of jack_delay which I didn't know about until
> a few minutes ago.
>
> http://boosthardware.com/pa-jack-latency-2.txt
>
> The results are better which is encouraging but the variation is still
> happening just on a smaller scale.
>

According to Fons Adriaensen the newer version gives more accurate results
because it uses 12 signal modes to make the measurement instead of 4 which
is what the older version of jack_delay uses.



--
Patrick Shirkey
Boost Hardware Ltd