May 7th, 2007


2.6.21 + alsa + dmix + sdl + 1 day = no sound

This problem has been around the systems I develop on for quite a while on one form or another, we want to do long term audio playing (like > 24 hours) and the system sits SDL on top of alsa and uses dmix for multiple processes (however it can reproduce with only one process using dmix...)

It used to be we would get a segfault after 24hours in alsa-lib but no the sounds just stops playing, I haven't done enough to narrow down whether it be alsa kernel, alsa lib, dmix or SDL's fault, however disabling dmix (which is what we normally do due to only having a single app) always works, however I now have a need to have two apps mixed together hence trying to fix dmix..

The hardware is Intel ICH6 with some Realtek ALC655 codec attached.

I'll probably start to debug in earnest quite soon..