real time question : RR vs FF?

[Stefan Kost]

Am 28.04.2011 05:34, schrieb Victor henri:
> Hello
> 
> I have made an app that displays the harmonics in 3d.
> 
> I want to be able to run it in real-time; I have used the 'rtpool-test' code
> from the gstreamer core examples (streams->rtpool-test.c) and it works. However,
> I have seen that this grants me a priority of 90 with a 'RR' policy. Is it
> possible to change the code code to get 'FIFO' policy? If yes, please how could
> I do this? I have tied to use the set_schedparam code, but I got the 'Invalid
> argument' during 'pthread_attr_setschedparam (&attr, &sched)' error... (as well
> as starting the app with 'chrt -r -p my-pid')

You need to have permission to swicth your app to that (e.g. try the chrt call
as root). Now the better question is why you want to do it. Before I go depper,
if would be good if you could tell what your expectation is.

Stefan

> 
> Another question : this code grants real time for Gstreamer code, but what about
> other code code (not Gstreamer) that follows it? The app is written like this :
> GTK GUI with a 'Play" button, that starts playing the sound with Gstreamer, and
> the 'spectrum' element send messages to the bus; everytime the "message handler"
> function retrives the values of the spectrum, there is a call to a function that
> display the values of the spectrum in a SDL/OpenGL window. My question is : is
> the display in the SDL/OpenGL window done also with the RR policy or back with
> TS policy?
> 
> When I run the app (its name is 'spectrum3d', then when I run 'ps -cLe' in a
> terminal to see all the threads of the app, I see this :
> 
>  5265  5265 TS   19 pts/0    00:00:01 spectrum3d
>  5265  5267 TS   19 pts/0    00:00:00 threaded-ml
>  5265  5268 TS   19 pts/0    00:00:00 threaded-ml
>  5265  5270 TS   19 pts/0    00:00:00 task0
>  5265  5271 TS   19 pts/0    00:00:00 spectrum3d
>  5265  5272 RR   90 pts/0    00:00:01 alsasrc:src
> 
> The 1st pid is the Gtk GUI; the last one must be the gstreamer sound reading,
> since its policy is RR; but I don't know what the other pid represent...
> 
> thanks for your help
> 
> Victor
> 
> 
> 
> _______________________________________________
> gstreamer-devel mailing list
> gstreamer-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel