[K12OSN] Why PA system mode?

[Jeff Siddall]

On 08/14/2011 03:09 PM, Burke Almquist wrote:
>
> On Aug 12, 2011, at 1:12 PM, Jeff Siddall wrote:
>
>> Anyone know why the clients run pulseaudio in system mode?  Here's an excerpt from the client system log:
>>
>> Aug  9 09:12:06 client-192 pulseaudio[1740]: main.c: OK, so you are running PA in system mode. Please note that you most likely shouldn't be doing that.
>> Aug  9 09:12:06 client-192 pulseaudio[1740]: main.c: If you do it nonetheless then it's your own fault if things don't work as expected.
>> Aug  9 09:12:06 client-192 pulseaudio[1740]: main.c: Please read http://pulseaudio.org/wiki/WhatIsWrongWithSystemMode for an explanation why system mode is usually a bad idea
>>
>> I did read http://pulseaudio.org/wiki/WhatIsWrongWithSystemMode and sure enough they say it is there for stuff like thin clients.  However, the reasons for it are really not that good: we _do_ have a real user, and things like home directories typically _aren't_ flushed on each session termination.
> But we don't have a "real" user on the thin clients, the real user is logged into the server, not the client, so that doesn't help us, since PA needs to run on the client for it to output the sound.
> If you were doing DRBL, where you network boot the OS, but all the apps are actually local, then system mode doesn't make sense, but you still need it on thin clients, since the user's session is actually on a different machine.

Yes, but...

The same user (both UID and name) logged in on the server is also 
present on the client -- with LTSP5 anyway.  Not sure about what magic 
happens behind the scenes but a custom /etc/passwd containing the real 
user is mounted as a tmpfs file on the client.  Have a look at a 
/etc/passwd on one of your logged in client to see what I mean.

So really the user is on both the client and server and as such it seems 
like pulse could run as the real user.

Maybe the system mode thing is a carryover from a time in the past 
(LTSP4 maybe?) where there were no real users on the client?  Can anyone 
confirm/deny this?

Thanks,

Jeff