-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Hello, I'm using non-blocking writes to play an audio stream. When snd_pcm_writei() return -EGAIN I put the thread to sleep for the time it would take to play the packet that I'm trying to write and the packet size it's capped at 1/4 the ALSA buffer so that should ensure that the buffer never gets more than half empty. And it works as I don't get underruns. But sometimes the audio gets choppy and it sounds like it's playing out of time. Like periodically for a fraction of a second it plays a bit of audio that should've been played about a second ago. Triggering an underrun or a call to snd_pcm_drain(), either by pausing the stream or overloading the CPU corrects the problem so I think the internal ALSA ring buffer pointers are getting out of sync somehow. Also it only happens with non-blocking writes. If I use blocking writes it works fine but there are other problems with that. So I think either I'm handling -EAGAIN incorrectly, or not configuring it properly? You can look at the code here: https://bitbucket.org/frodzdev/mediabox/src/84dced5b84eba4e6e639615dd3d30fccfb0c805b/src/audio.c?at=staging&fileviewer=file-view-default#audio.c-503 Any help will be appreciated. - -- Fernando Rodriguez -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJYDjCvAAoJEPbOFX/5UlwcG/MP/2WAuJKy4WhU5h/yauDyuv1S h5H2Lj2orQcx0R55Qy3xewYz+HEgM+k0p2chJXUsB7dxp6zrnXCven1H0lZqhm0o dVFZ+E3r/rUBpfIOmlvT27uUTFyQcdz9h+WViAFvCbldEOEa7DALEXqLvNLeC1S7 C6dfuV/L7/Dq0W5sNtErZpzH7YY715zzZCIGncAd7LGteTaMND/p6F02CqwEm343 E4zNL6+Ac3N1eEmlRWI/Vo8QC1Yafo7BbPuR0kYornkqigNgK3yL/+FSwAcHZC4V Ge8Q0Ba1DCFMWC6BEfPwSyZ4hUeillQQbPMYhgu4QCKiKUrD8QOFSu16e2A1d+hU usn9WQwyisheDavqxvNN+6pr2Gi9r2BxzWbqLQKJ8L+bSLvuaDGEWmUDgVjjGm89 NKcL6yjucJamjjn8ZMfcx6T4e+ieyU9IOMNteXz54QKG9ltX2IqWgoBG6S+S4cjL SggGePoQHq2e7WwWjKqDQ5lOx0aZsb5SZqrgllR4/ROL4Dk+52DRjYChdOG4Prim kFRmcdHrvlBmunCXIaIu5+Ec0GuoBEjPfTKwlo1gylrZEYAfjU8iLpoTDkP3J4SK FPY5ibUD9IKF/cbdFUzx+oAZoBFlC3oAPLqt80VgsLVEI/1d9Z36+xPRE6PidihP Orn2dggcwqfbR1v+x+Ot =RfWT -----END PGP SIGNATURE----- _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
