Alsa callback stops fireing for a few second in case of underflow

[mixxxbot]

Reported by: daschuer
Date: 2014-04-21T10:41:39Z
Status: New
Importance: High
Launchpad Issue: lp1310553
Tags: engine, performance, portaudio

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This happens with low audio buffer sizes and realtime scheduling.

We should really sure what is going on here, because this could likely be a party stopper, when using effects and key-lock on a four deck setup.

Tested at Ubuntu Saucy 64bit.

[mixxxbot]

Commented by: daschuer
Date: 2014-04-21T11:12:48Z

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It happens only at 2,9 ms audio buffer, not at 1,45 ms, not at 5,8 ms.
The audio thread does not return from a poll() inside PA / Alsa.

[mixxxbot]

Commented by: daschuer
Date: 2014-04-21T13:23:35Z

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It seams not to be directly connected to the CPU load.
I am currently using Mixxx at 2.9 ms during my tests and i experience this bug also if keylock is disabled.

[mixxxbot]

Commented by: ywwg
Date: 2014-12-31T21:39:23Z

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daniel are you still seeing this?

[mixxxbot]

Commented by: daschuer
Date: 2015-01-01T13:51:32Z

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Yes, on my current Upuntu Trusty setup cannot use 2.9 ms at all, but 1.45