On 2010-06-24 08:42, Takashi Iwai wrote:
At Wed, 23 Jun 2010 21:57:01 +0200, David Henningsson wrote:
These two patches are being used in Ubuntu Lucid (released this April) and are working well enough to have people asking us to backport them to Karmic. Today I got an email, asking for the upstream status of one of these patches, since he wanted them in Fedora. If posting them here isn't the correct way to upstream them, please tell me so.
The first one (Fix invalid buffer pointer return value) fixes broken logic:
This patch improves recovering from underruns, and prevents hangs inside snd_pcm_write* and snd_pcm_read* due to snd_pcm_avail* returning too low values. It especially helps low latency situations.
This one looks OK. Applied now.
Thanks!
The second one (Do not report underruns to the ALSA layer) is more a change of behavior, which could be questioned. The arguments for removing that code are these:
- If pulseaudio gets an underrun, the normal way to end that underrun
is to feed it with more buffers. This is different from the ALSA way of dealing with underruns, which requires hardware buffer pointers to be reset.
- In addition, underrun signals are delivered asynchronously from
pulseaudio. This means that there might be more buffers on the way to pulseaudio when the underrun is reported, making the underrun obsolete. Unfortunately, there is currently no known way to determine whether this is the case or not.
I think this helps for normal use-cases, so it'd be good to apply. But, I prefer having a runtime option for such a behavior change (although the default value can be the new behavior).
Care to add it?
Sure, I can do that - it sounds like a good idea to have it configurable. Just so I understand you right, exactly how do you expect the user / application to configure it?
// David