On 08/20/2011 06:12 PM, Tanu Kaskinen wrote: > On Fri, 2011-08-19 at 14:08 +0530, Himanshu Chug wrote: >> Hi All >> >> I am able to get the small beep files working consistently using gst-launch >> now by modifying tsched_buffer_size param of module-alsa-sink like: >> >> load-module module-alsa-sink tsched_buffer_size=1024, >> (buffer size is default to 2s) >> >> I am using timer based tsched audio scheduling , on OMAP4 platform. >> >> I have few questions: >> >> Q1. how does this change affect my system, if I always make >> tsched_buffer_size=1024? I suspect it may increase the power >> consumption and increase the ALSA >> wakeup's , if I reduce the buffer size and period like like this? > > Yes. > >> Q2. When the beep file is not played on speakers , I can see a lot of rewind >> prints from PA >> protocol-native.c: Requesting rewind due to rewrite. and it continues and >> finally I got EOS from my gst pipeline >> >> I need to know what is rewind ? and what triggers PA to make these rewinds? > > As the log message says, the rewrites cause the rewinds. > >> and what is "rewrite" here in terms of pulseaudio? > > It means rewriting part of the sink (hw) buffer. If that log message > appears, it means that the client has written data to a position that > requires a part of the sink's buffer to be overwritten, and thus a > rewind is needed. > >> (Just to remind you I can play the beep wav with paplay and pacmd >> play-file, without any issues and without modifying the buffersize param. >> so I am just confused whats going here ? ) > > So did you find out whether your system has David's patches that I > referred to in my previous reply? If you did, and the patches are > applied, then there's still something to fix in Pulseaudio's and > Gstreamer's interaction. Btw, I posted an improved version of the patch a few days ago to the gstreamer mailinglist, and it has been committed. See http://cgit.freedesktop.org/gstreamer/gst-plugins-good/commit/ext/pulse/pulsesink.c?id=e70020b45630d99132a99892ecc6e1dcd1ce6f8a Hopefully that can help. -- David Henningsson, Canonical Ltd. http://launchpad.net/~diwic
