[pulseaudio-discuss] PulseAudio Painfully Slow

[Alexander E. Patrakov]

14.07.2014 02:24, Benny de von Ausfern wrote:
> All the mentioned games run natively, with the exception being Dungeons
> & Dragons Online (which runs fine with ALSA). This is certainly not a
> Wine bug. I want you to understand that "killall -9 pulseaudio"
> immediately solves all the problems, so its nothing but natural to blame
> pulseaudio.
>
> This is my /proc/cpuinfo: http://pastebin.com/CqccL3qm
> alsa-inf.sh: http://pastebin.com/8zC6fdhh

Looked. Your ALSA configuration is broken.

First, you have a Haswell HDMI audio device in the system. Mere presence 
of it in some kernel configurations causes IRQ-related issues that can 
delay arbitrary programs for arbitrary amount of time if it is accessed 
at least once. This is a known kernel bug, tracked as 
https://bugzilla.kernel.org/show_bug.cgi?id=60769 (but for other 
reporters it has different manifestations). With pure ALSA, you don't 
hit it, because nothing accesses this device even for probing the 
capabilities.

Please add this to the kernel command line to work around the kernel bug:

intel_iommu=igfx_off

Second, you have overrides of the model that are unnecessary for your 
hardware. 6stack is definitely not applicable to Haswell HDMI. So, 
remove all snd-hda-intel module parameters.

Please fix the problems above and see whether the game-framerate bug 
still exists.

> Pulseaudio is around 6% usage. When there is a game running, sometimes
> the thing propagates to the WM (Enlightenment DR 18 with all the
> compositions disabled, I don't like them) itself - windows lag when I
> try to move/resize, take longer to open or freeze for a couple of
> seconds without reason. Once again: killing pulseaudio solves it
> IMMEDIATELY. I've never had this behaviour without pulseaudio. As a
> matter of fact, I can play 2 or 3 of those games simultaneously (I have
> 2 screens) with ALSA without any noticeable slowdown.
>
> top with Audacious playing music: http://pastebin.com/8eBbus7k
> top with Skype (and nothing else going on): http://pastebin.com/DyJ0vJWC

It is not "with nothing else going on" - there is pavucontrol, which 
causes PulseAudio to enable the peak meter. And with that, it's 
perfectly reasonable for PulseAudio to eat 6% of your CPU.

-- 
Alexander E. Patrakov