[pulseaudio-discuss] [PATCH] Change the default fragment size to 5 ms

[Alexander E. Patrakov]

24.10.2014 00:35, I wrote:
> 23.10.2014 23:27, Arun Raghavan wrote:
>> I've not looked at the Wine code for this, but I wonder if we can
>> guess this by looking at the minreq/tlength values that are returned.
>
> Unpatched Wine just uses ALSA, so, your question is more about the ALSA
> plugin.
>
> Indeed, for native PulseAudio clients, it is possible to use
> pa_stream_get_buffer_attr() once the stream is connected, and winepulse
> patches indeed contain such call. The ALSA plugin does not call this
> function. So, this is indeed part of the problem.

I have to correct myself. The ALSA plugin has no way to call this function.

This is because it needs to communicate the "correct" buffer metrics to 
the program when returning from pulse_hw_params(). However, that 
function only stores the buffer metrics, and, on return, there is no 
stream yet. The stream is connected (and thus the buffer metrics are 
known) in pulse_prepare(), i.e. much later than it would be needed to 
communicate the actual metrics to the client.

-- 
Alexander E. Patrakov