Hi Clemens, >> When PulseAudio is used and all PCM is routed through PulseAudio >> (Fedora, Meego, etc), the notion of ALSA periods isn't very useful. >> So why not disable them entirely to reduce the number of wakeups? ... >> There are probably some cases where you don't want this type of >> behavior (broken hardware, legacy code with multiple-buffering, >> disabled timer in PulseAudio), > > It's interesting that all ALSA applications except PA are "legacy". ?:) Ha. Nice slip. I didn't mean legacy was bad... It's perfectly ok to use multiple buffers and interrupts in a variety of apps. >> so I think it would make sense to request the disabling of interrupts >> when hw_params are set, since this is also the time when period sizes >> are set. > > Yes. ?For compatibility with the existing ALSA API, this needs to be > a flag that is not enabled by default. Agreed. This shouldn't even be mandatory since this option might not be possible in all platforms. >> I am aware that some changes would be needed in pcm_lib.c, where all >> the error checks are done. > > Plus all the API changes in the ALSA kernel framework, the ALSA kernel/ > userspace interface, and the alsa-lib interface. I am not following this point. If you add a simple flag to an existing interface, why would we need to change the kernel/userspace inferface? This change should be possible in a backwards compatible manner as an additional option provided to the application developer. Cheers -Pierre
