On Sun, 23 Aug 2009 11:25:09 -0400 Steve Blackwell zephod@cfl.rr.com wrote:

I am not a pulse expert, but will take a stab at this as I have been wrestling with it for a while.

I can't find any reference to pulseaudio in any init file

Not init. You can configure it to start a systemwide server, which I suspect is started by X.

So where does it get started?

If you are using the default Fedora setup, you have your own version of pulse started when you log in. I notice that it also can be started by programs that need its services, and that seems to be gconf-helper.

No representation as to validity of the above, might contain wild supposition and unsubstantiated misinformation. If you want pulse information, go to the horses mouth http://www.pulseaudio.org/

stan wrote:

If you are using the default Fedora setup, you have your own version of pulse started when you log in. I notice that it also can be started by programs that need its services, and that seems to be gconf-helper.

Isn't "autospawn" activated by default in /etc/pulse/client.conf? That means you can have pulseaudio started by who knows what.

On 08/26/09 13:03, quoth Jonathan Ryshpan:

On Wed, 2009-08-26 at 09:25 +0200, Roberto Ragusa wrote:

...

stan wrote:

...

If you are using the default Fedora setup, you have your own version of pulse started when you log in. I notice that it also can be started by programs that need its services, and that seems to be gconf-helper.

Isn't "autospawn" activated by default in /etc/pulse/client.conf? That means you can have pulseaudio started by who knows what.

I don't think so. On my system (Fedora-11 vanilla) autospawn is commented out.

jon

Ok. Why do you think it's commented out?

I'm looking at my copy and the comments in the top of the file begin with a #sign but the config lines begin with a semi;colon. So right now I have no idea what's a comment and what's required syntax.

Can pulseaudio be simply shut OFF? This thing really stinks.

Steven W. Orr wrote:

On 08/26/09 13:03, quoth Jonathan Ryshpan:

...

On Wed, 2009-08-26 at 09:25 +0200, Roberto Ragusa wrote:

...

stan wrote:

...

If you are using the default Fedora setup, you have your own version of pulse started when you log in. I notice that it also can be started by programs that need its services, and that seems to be gconf-helper.

Isn't "autospawn" activated by default in /etc/pulse/client.conf? That means you can have pulseaudio started by who knows what.

I don't think so. On my system (Fedora-11 vanilla) autospawn is commented out.

jon

Ok. Why do you think it's commented out?

I'm looking at my copy and the comments in the top of the file begin with a #sign but the config lines begin with a semi;colon. So right now I have no idea what's a comment and what's required syntax.

Can pulseaudio be simply shut OFF? This thing really stinks.

It works for most people, Steven. Some people (myself included) have had issues with it, but that doesn't mean it "really stinks."

It's started in your session. If you're using Gnome, go to

System->Preferences->Startup Applications

and scroll down the list. You can uncheck the box next to "PulseAudio Sound System" to not have it start up, or delete it entirely. There's undoubtedly a similar thing for KDE, but since I'm not a KDE user, I don't know where it is. Someone else want to chime in? ---------------------------------------------------------------------- - Rick Stevens, Systems Engineer ricks@nerd.com - - AIM/Skype: therps2 ICQ: 22643734 Yahoo: origrps2 - - - - If it's stupid and it works...it ain't stupid! - ----------------------------------------------------------------------

On Wed, 26 Aug 2009 12:21:20 -0700 Rick Stevens ricks@nerd.com wrote:

It's started in your session. If you're using Gnome, go to

 System->Preferences->Startup Applications

and scroll down the list.

Ah-ha! There's the answer. On my F10 system it is

System->Preferences->Personal->Sessions

but there is an entry for PA. Now, what I'd like to know is where is the file that stores this info and what reads it when I login. Back in the day it used to be Xsession or something like that.

Thanks Rick, Steve

Ok Steven, let me do a google search on "pulseaudio home page", follow the first link which reads www.pulseaudio.org, click on the "documentation" link, scroll down to "KDE" and read http://www.pulseaudio.org/wiki/PerfectSetup#KDE for you here. It says:

<quote> KDE 4 uses Phonon as the main audio interface. The Xine backend of Phonon should eventually use PulseAudio automatically, but at the time of writing the pulse plugin for Xine is too unreliable, so it's disabled by default. While waiting for that to get better, Phonon uses Alsa. Therefore, to get Phonon to use PulseAudio, you have to edit your ~/.asoundrc or /etc/asound.conf. </quote>

So when your favorite KDE app tries to play some sound, it talks to Phonon, which either uses xine backend to talk to pulseaudio directly, or uses alsa. Now let me scroll back to the top of the page and read http://www.pulseaudio.org/wiki/PerfectSetup#ALSAApplications for you:

<quote> If the PulseAudio plugin for alsalibs is installed all applications with support for the ALSA API should be able to access a PulseAudio server. You need version 1.0.12 or newer of the ALSA packages for the PulseAudio plugin to be included.

To activate the driver edit /etc/asound.conf or ~/.asoundrc and add:

pcm.pulse { type pulse }

ctl.pulse { type pulse }

Now you you can access the PulseAudio server under the virtual ALSA device pulse:

% aplay -Dpulse foo.wav % amixer -Dpulse

If you want to make the PulseAudio driver the default, use something like this in the ALSA configuration files:

pcm.!default { type pulse } ctl.!default { type pulse } </quote>

Now let me take a look at /etc/asound.conf and ~/.asoundrc instead of you, and find that this is precisely how a default Fedora system is configured.

So how does it work? Open your favorite sound app, and ask it to play some music. If it is a typical KDE app, it will utilize Phonon, which redirects to ALSA, where pulseaudio plugin for alsa takes over, checks if the pulseaudio binary is already running and transfers audio handling to it. If it is not running, the plugin launches /etc/pulse/default.pa, which is an equivalent of an userland "init script" for pulseaudio. It launches the actual binary. Look at the first line:

#!/usr/bin/pulseaudio -nF

This is where it actually gets executed. (I hope you are familiar with the "sha-bang" syntax.)

Now, once executed, pulseaudio starts receiving signals to be played from all apps that try to use it natively, or try to use ALSA or ESD or Phonon or whatever. All these signals get mixed and sent to ALSA sound driver which talks to actual hardware to play the sound.

So in a nutshell, whatever your app tries to use as a sound interface, it gets eventually rerouted to pulseaudio, which gets executed if it is not running already. If it doesn't get rerouted to pulseaudio, something is broken (typically the app itself), and you don't get any sound from that app by default. File a bug against it.

...

...

Can pulseaudio be simply shut OFF?

I don't think so, at least not so easily. As you can see above, it is way too much integrated in the system. There is no single place where it is invoked and where it could be "shut off". You need to uninstall it altogether and let every app find it's own way to fallback to alsa.

Unfortunately, I am running KDE-4.2.4 and if there's a way to shut the little stinker off, I'd be grateful to know how.

AFAICS, KDE is using Xine backend by now, which talks to pulseaudio natively. I don't think that you can find an option to shut it down and use alsa. But do take a look at systemsettings -> Multimedia, maybe there you can set preferences the way you like. Here I talk about the latest KDE 4.3, you should probably yum update.

I have no idea what it is that pulseaudio is supposed to actually do that I'm supposed to like about it. I used to have sound. I still have sound.

Let me read the very first sentence from http://www.pulseaudio.org/ for you:

<quote> PulseAudio is a sound server for POSIX and Win32 systems. A sound server is basically a proxy for your sound applications. It allows you to do advanced operations on your sound data as it passes between your application and your hardware. Things like transferring the audio to a different machine, changing the sample format or channel count and mixing several sounds into one are easily achieved using a sound server. </quote>

Then let me click on "About pulseaudio" link and read http://www.pulseaudio.org/wiki/AboutPulseAudio#Details for you:

<quote> PulseAudio is a networked sound server, similar in theory to the Enlightened Sound Daemon (EsounD). PulseAudio is however much more advanced and has numerous features.

A sound server can serve many functions:

* Software mixing of multiple audio streams, bypassing any restrictions the hardware has. * Network transparency, allowing an application to play back or record audio on a different machine than the one it is running on. * Sound API abstraction, alleviating the need for multiple backends in applications to handle the wide diversity of sound systems out there. * Generic hardware abstraction, giving the possibility of doing things like individual volumes per application. </quote>

In a nutshell, pulseaudio is for audio what X is for graphics. Imagine every particular app having to talk directly to radeon, intel or nvidia drivers in order to display itself on the screen. It is extremely complicated to maintain such an app. X is an abstraction layer that provides a standardized graphics interface to each app, and talks to the drivers in the background, "mixing the signals" of all apps into a set of windows that you can see on the screen.

Pulseaudio does the same thing, for audio. The way I see it, it is a Good Thing, providing a lot of functionality.

Finally, this is how top reports the cpu usage on my system at the moment:

12.0% X 7.6% plasma-desktop 6.0% xmms 5.0% pulseaudio 3.3% ktorrent 1.7% compiz

I am running compiz-fusion/emerald under latest KDE, have a bunch of windows open on 8 desktops, listening to mp3 in xmms, while downloading some stuff with ktorrent. Now, if you compare the cpu usage by X and by pulseaudio, I think I should "turn off" X first, before pulseaudio, if I were to follow your logic.

You never listen to several audio sources simultaneously, right? So you don't need pulseaudio server, right? I guess you also never look at two windows on the screen simultaneously, right? So you don't actually need X, right?

I am sorry if this e-mail sounds a bit like venting, but *please* next time use google and read about things yourself, don't expect from people on the list to quote things that can be found on the web (and in a rather obvious way).

HTH, :-) Marko

On 08/26/09 20:45, quoth Marko Vojinovic:

Ok Steven, let me do a google search on "pulseaudio home page", follow the first link which reads www.pulseaudio.org, click on the "documentation" link, scroll down to "KDE" and read http://www.pulseaudio.org/wiki/PerfectSetup#KDE for you here. It says:

<quote> KDE 4 uses Phonon as the main audio interface. The Xine backend of Phonon should eventually use PulseAudio automatically, but at the time of writing the pulse plugin for Xine is too unreliable, so it's disabled by default. While waiting for that to get better, Phonon uses Alsa. Therefore, to get Phonon to use PulseAudio, you have to edit your ~/.asoundrc or /etc/asound.conf. </quote>

So when your favorite KDE app tries to play some sound, it talks to Phonon, which either uses xine backend to talk to pulseaudio directly, or uses alsa. Now let me scroll back to the top of the page and read http://www.pulseaudio.org/wiki/PerfectSetup#ALSAApplications for you:

<quote> If the PulseAudio plugin for alsalibs is installed all applications with support for the ALSA API should be able to access a PulseAudio server. You need version 1.0.12 or newer of the ALSA packages for the PulseAudio plugin to be included.

To activate the driver edit /etc/asound.conf or ~/.asoundrc and add:

pcm.pulse { type pulse }

ctl.pulse { type pulse }

Now you you can access the PulseAudio server under the virtual ALSA device pulse:

% aplay -Dpulse foo.wav % amixer -Dpulse

If you want to make the PulseAudio driver the default, use something like this in the ALSA configuration files:

pcm.!default { type pulse } ctl.!default { type pulse }

</quote>

Now let me take a look at /etc/asound.conf and ~/.asoundrc instead of you, and find that this is precisely how a default Fedora system is configured.

So how does it work? Open your favorite sound app, and ask it to play some music. If it is a typical KDE app, it will utilize Phonon, which redirects to ALSA, where pulseaudio plugin for alsa takes over, checks if the pulseaudio binary is already running and transfers audio handling to it. If it is not running, the plugin launches /etc/pulse/default.pa, which is an equivalent of an userland "init script" for pulseaudio. It launches the actual binary. Look at the first line:

#!/usr/bin/pulseaudio -nF

This is where it actually gets executed. (I hope you are familiar with the "sha-bang" syntax.)

Now, once executed, pulseaudio starts receiving signals to be played from all apps that try to use it natively, or try to use ALSA or ESD or Phonon or whatever. All these signals get mixed and sent to ALSA sound driver which talks to actual hardware to play the sound.

So in a nutshell, whatever your app tries to use as a sound interface, it gets eventually rerouted to pulseaudio, which gets executed if it is not running already. If it doesn't get rerouted to pulseaudio, something is broken (typically the app itself), and you don't get any sound from that app by default. File a bug against it.

...

...

...

Can pulseaudio be simply shut OFF?

I don't think so, at least not so easily. As you can see above, it is way too much integrated in the system. There is no single place where it is invoked and where it could be "shut off". You need to uninstall it altogether and let every app find it's own way to fallback to alsa.

...

Unfortunately, I am running KDE-4.2.4 and if there's a way to shut the little stinker off, I'd be grateful to know how.

AFAICS, KDE is using Xine backend by now, which talks to pulseaudio natively. I don't think that you can find an option to shut it down and use alsa. But do take a look at systemsettings -> Multimedia, maybe there you can set preferences the way you like. Here I talk about the latest KDE 4.3, you should probably yum update.

...

I have no idea what it is that pulseaudio is supposed to actually do that I'm supposed to like about it. I used to have sound. I still have sound.

Let me read the very first sentence from http://www.pulseaudio.org/ for you:

<quote> PulseAudio is a sound server for POSIX and Win32 systems. A sound server is basically a proxy for your sound applications. It allows you to do advanced operations on your sound data as it passes between your application and your hardware. Things like transferring the audio to a different machine, changing the sample format or channel count and mixing several sounds into one are easily achieved using a sound server. </quote>

Then let me click on "About pulseaudio" link and read http://www.pulseaudio.org/wiki/AboutPulseAudio#Details for you:

<quote> PulseAudio is a networked sound server, similar in theory to the Enlightened Sound Daemon (EsounD). PulseAudio is however much more advanced and has numerous features.

A sound server can serve many functions:

* Software mixing of multiple audio streams, bypassing any restrictions 

the hardware has. * Network transparency, allowing an application to play back or record audio on a different machine than the one it is running on. * Sound API abstraction, alleviating the need for multiple backends in applications to handle the wide diversity of sound systems out there. * Generic hardware abstraction, giving the possibility of doing things like individual volumes per application.

</quote>

In a nutshell, pulseaudio is for audio what X is for graphics. Imagine every particular app having to talk directly to radeon, intel or nvidia drivers in order to display itself on the screen. It is extremely complicated to maintain such an app. X is an abstraction layer that provides a standardized graphics interface to each app, and talks to the drivers in the background, "mixing the signals" of all apps into a set of windows that you can see on the screen.

Pulseaudio does the same thing, for audio. The way I see it, it is a Good Thing, providing a lot of functionality.

Finally, this is how top reports the cpu usage on my system at the moment:

12.0% X 7.6% plasma-desktop 6.0% xmms 5.0% pulseaudio 3.3% ktorrent 1.7% compiz

I am running compiz-fusion/emerald under latest KDE, have a bunch of windows open on 8 desktops, listening to mp3 in xmms, while downloading some stuff with ktorrent. Now, if you compare the cpu usage by X and by pulseaudio, I think I should "turn off" X first, before pulseaudio, if I were to follow your logic.

You never listen to several audio sources simultaneously, right? So you don't need pulseaudio server, right? I guess you also never look at two windows on the screen simultaneously, right? So you don't actually need X, right?

I am sorry if this e-mail sounds a bit like venting, but *please* next time use google and read about things yourself, don't expect from people on the list to quote things that can be found on the web (and in a rather obvious way).

Marko, I thank you for your help. I had read the pa material before but I did not realize that removing it from the system was really not an option. After reading your reply, I upgraded to kde-4.3.0 and that actually made a huge difference. Time will tell, but so far, I do not seem to be getting syslog messages constantly at a rate of about 26 per second. The messages now seem to be only happening when I do something that causes a sound to be generated, and it stops after a second or two with a rate of about 13/second. This is a substantial improvement.

I *might* not be feeling so grateful if your answer had not coincided with an upgrade that showed such an improvement ;-) but since it worked out as well as it did, I say we declare victory and withdraw. There's a beer waiting for you if you get to the Boston area. :-)>

On Thu, 27 Aug 2009 09:40:24 +0100 Marko Vojinovic vvmarko@gmail.com wrote:

On Thursday 27 August 2009 05:16:33 Steven W. Orr wrote:

...

Marko, I thank you for your help. I had read the pa material before but I did not realize that removing it from the system was really

That's good news, I'm glad you got it working better! :-)

Ahem! Can we get back to the subject line?

So far we've established that pulsaaudio is started when you log in and that you can turn it off by going to

System->Preferences->Personal->Sessions

if you have F10 and

System->Preferences->Startup Applications

if you have F11. I'd like to know where (which file) the information is stored in and what program starts it. gdm? gnome? gconf?

Thanks, Steve

On 09-08-27 10:12:44, Steve Blackwell wrote: ...

... I'd like to know where (which file) the information isstored in and what program starts it. gdm? gnome? gconf?

Look in ~/.config.

See http://library.gnome.org/devel/autostart-spec/

Hi;

On Thu, 2009-08-27 at 14:49 -0400, Steve Blackwell wrote:

On Fri, 28 Aug 2009 00:12:39 +0930 Tim ignored_mailbox@yahoo.com.au wrote:

The pulseaudio.desktop file contains this:

[Desktop Entry] Version=1.0 Encoding=UTF-8 Name=PulseAudio Sound System Comment=Start the PulseAudio Sound System Exec=start-pulseaudio-x11 Terminal=false Type=Application Categories= GenericName= Name[en_US]=PulseAudio Sound System Comment[en_US]=Start the PulseAudio Sound System X-GNOME-Autostart-enabled=false

/usr/bin/start-pulseaudio-x11 is a script:

<comments snipped> set -e

# Exit without running pulseaudio daemon if this is a remote desktop session [ -n "$PULSE_SERVER" ] && exit 0

/usr/bin/pulseaudio --start "$@"

if [ x"$DISPLAY" != x ] ; then

/usr/bin/pactl load-module module-x11-publish "display=$DISPLAY"
> /dev/null

if [ x"$SESSION_MANAGER" != x ] ; then

/usr/bin/pactl load-module module-x11-xsmp "display=$DISPLAY session_manager=$SESSION_MANAGER" > /dev/null fi fi

So my remaining questions are what reads the pulseaudio.desktop file and how does pulseaudio get started if it does not exist.

Steve

I have been following this thread with a great deal of interest. When you finally get it figured out would you please be sure to let us all know.

At 14:49 on 27 Aug 2009, Steve Blackwell wrote:

On Fri, 28 Aug 2009 00:12:39 +0930 Tim ignored_mailbox@yahoo.com.au wrote:

...

On Thu, 2009-08-27 at 10:12 -0400, Steve Blackwell wrote:

...

I'd like to know where (which file) the information is stored in and what program starts it. gdm? gnome? gconf?

A hint for finding out things like that: Change a setting, and search for a very recently changed file.

Interesting. I had already found a directory called ~/.config/autostart but there was no hint of anything pulseaudio related in there. Then I followed your suggestion and disabled its autostart and searched for recently changed files. Now there is a file called ~/.config/pulseaudio.desktop. That is backward to what I would have expected and if I enable pulseaudio again, the file is removed.

Come on, it's not exactly rocket-science. Perhaps you could start by reading what you've posted:

The pulseaudio.desktop file contains this:

[Desktop Entry]

<snip>

X-GNOME-Autostart-enabled=false

Look also in /etc/xdg/autostart/ and at http://standards.freedesktop.org/autostart-spec/autostart-spec-latest.html

On Wed, Aug 26, 2009 at 13:03, Jonathan Ryshpan jonrysh@pacbell.net wrote:

On Wed, 2009-08-26 at 09:25 +0200, Roberto Ragusa wrote:

...

stan wrote:

...

If you are using the default Fedora setup, you have your own version of pulse started when you log in. I notice that it also can be started by programs that need its services, and that seems to be gconf-helper.

Isn't "autospawn" activated by default in /etc/pulse/client.conf? That means you can have pulseaudio started by who knows what.

I don't think so. On my system (Fedora-11 vanilla) autospawn is commented out.

"autospawn" is the default setting. They listed in the file anyway for documentary purposes.

In order to disable it, you would un-comment that line and set it manually.

-Ryan

On Tuesday 01 September 2009 15:56:30 Steve Blackwell wrote:

Some people had asked to keep this thread going so here is what I've found so far. (Note That I'm using GNOME and GDM so I started with GDM. There is, no doubt, something for equivalent KDE)

[snip]

My conclusion so far is that pulseaudio is started by autostart and that the /etc/xdg/autostart/*.desktop files are called from within gnome-session. I need to research gnome-session next.

The actual pulseaudio binary is executed by the script /etc/pulse/default.pa (at the very first line), so maybe you can do a full-text search on gnome config files and scripts to find out where is this script being invoked. I don't use gnome, so can't help much on that.

And yes, keep the thread going. As for me, I don't want to disable pulseaudio (it Just Works on my machine), but am interested in understanding the details of its invocation and interaction with the rest of the system.

HTH, :-) Marko