[LAU] OnDemand-performance was(OT: klang)

Len Ovens len at ovenwerks.net
Sun Aug 5 19:14:45 UTC 2012

On Sun, August 5, 2012 8:01 am, Ralf Mardorf wrote:
> On Sun, 2012-08-05 at 07:12 -0700, Len Ovens wrote:
>> I have another idea... I make use of the system runlevels. Ubuntu only
>> uses runlevels 0,1,2 and 6.
> What runlevels will Ubuntu Studio have got, when Ubuntu makes the switch
> to systemd?

Both upstart (which Ubuntu uses now) and systemd are compatable with init.
I am in fact using upstart scripts now for my runlevel changes and because
many of the services I want to control are already upstart scripts (ie.
cron and mysql). Even with these new tools for doing what init used to,
the idea of operating modes is still there. It would be possible to change
RL 0 to halt.mode and RL 1 or S to single.mode, but even if that happens
it should be possible to create a new mode called audio.mode. However, I
don't see that happening because both upstart and systemd are created to
allow parallel processing and daemon startup rather than the serial
approach init uses. There seems to be no move to get rid of any of the
operating modes being used now. We still need an orderly startup and

> Writing a script and use it with a button for the panel IMO is the
> better way to go. Resp., everybody building customized kernels directly
> could disable anything, but performance.

Using a button from a panel is the way I like it, but I have talked to
people who feel differently and would like it to start when jackd does.
The way I am putting together can be used either way. The system side
things have to be separate anyway... so the systray script actually runs a
cli command that can just as easily be started by qjackctl or a session
manager at need. I actually have 4 RL set up normal/audio/graphics/video.
but they could just as easy be
normal/audiofullspeed/audiohalfspeed/audioanotherspeed. (and as far as I
know it would be possible to add RL7 if that was not enough.... though I
honestly don't know how upstart or systemd would handle those... init

Rather than build a special kernel I would just change
/etc/init.d/ondemand to set performance... it would just take changing one
word in one file. However, because I have heard of (not experienced)
systems shutting themselves down due to overheating when run too hard I
don't want to suggest that as a blanket solution. I also feel that being
able to run at a lower speed that allows the machine to run with fans off
is valuable too. The recording can be at low speed and the post production
at full.

By the way, runlevel switching seems like a non-event to the user so long
as the runlevel chosen does not shut the session/X down. Of course if the
user is using something that gets shutdown (like wireless in my case) it
would be noticed.

My next step is to create a gui that allows the user to choose what to
shutdown when. This will take more time that everything I have figured out
so far.

> 2 Cents,

Don't know if anything I say has monetary value... The one worthwhile
thing I learned in tech school was:
The more you know, the more you know you don't know.

Len Ovens

More information about the Linux-audio-user mailing list