Can not play audio with screen off
Hi!
I'm playing some more with N900, this time I'd like to use it as a alarm clock...
And now I realized I can not, because system performance is so horrible with screen off that mpg123 + pulseaudio skips horribly. This is without tweaking serial parameters, so CPU is definitely not going into the idle/off modes.
Loading CPU fixes the issue (I used cat /dev/zero > /dev/null).
Hmm. And it seems to work better if I ssh in and launch mpg123 remotely. Weird.
Kernel 4.5-rc0. Will try on different ones.
Any ideas? Is there interface to tell kernel that better performance is needed for a while?
Thanks,
Pavel
Signature · 2 lines
(english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
Quoted 12 lines · Pavel Machek
Hi!
I'm playing some more with N900, this time I'd like to use it as a alarm clock...
And now I realized I can not, because system performance is so horrible with screen off that mpg123 + pulseaudio skips horribly. This is without tweaking serial parameters, so CPU is definitely not going into the idle/off modes.
Loading CPU fixes the issue (I used cat
/dev/zero>/dev/null).
Quoted 8 lines
Hmm. And it seems to work better if I ssh in and launch mpg123 remotely. Weird.
Kernel 4.5-rc0. Will try on different ones.
Any ideas? Is there interface to tell kernel that better performance is needed for a while?
pm_qos cpu_dma_latency? Drivers will have to be properly instrumented with appropriate latency values -> this will control the depth in C states that the system will attempt. NOTE: it is a dual edged sword, bad configurations can result in none of the C-states being entered.
Signature · 2 lines
Regards, Nishanth Menon
Hi!
Quoted 15 lines
Quoted 15 lines
I'm playing some more with N900, this time I'd like to use it as a alarm clock...
And now I realized I can not, because system performance is so horrible with screen off that mpg123 + pulseaudio skips horribly. This is without tweaking serial parameters, so CPU is definitely not going into the idle/off modes.
Loading CPU fixes the issue (I used cat
/dev/zero>/dev/null).Hmm. And it seems to work better if I ssh in and launch mpg123 remotely. Weird.
Kernel 4.5-rc0. Will try on different ones.
Quoted 7 lines
Quoted 2 lines
Any ideas? Is there interface to tell kernel that better performance is needed for a while?
pm_qoscpu_dma_latency? Drivers will have to be properly instrumented with appropriate latency values -> this will control the depth in C states that the system will attempt. NOTE: it is a dual edged sword, bad configurations can result in none of the C-states being entered.
Ok, so far it looks like artefact of -rc0 kernel. Lets see if it reappers...
Thanks,
Pavel
Signature · 2 lines
(english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
Hi!
Quoted 18 lines
Quoted 17 lines
Quoted 17 lines
I'm playing some more with N900, this time I'd like to use it as a alarm clock...
And now I realized I can not, because system performance is so horrible with screen off that mpg123 + pulseaudio skips horribly. This is without tweaking serial parameters, so CPU is definitely not going into the idle/off modes.
Loading CPU fixes the issue (I used cat
/dev/zero>/dev/null).Hmm. And it seems to work better if I ssh in and launch mpg123 remotely. Weird.
Kernel 4.5-rc0. Will try on different ones.
Any ideas? Is there interface to tell kernel that better performance is needed for a while?
Quoted 7 lines
Quoted 4 lines
pm_qoscpu_dma_latency? Drivers will have to be properly instrumented with appropriate latency values -> this will control the depth in C states that the system will attempt. NOTE: it is a dual edged sword, bad configurations can result in none of the C-states being entered.Ok, so far it looks like artefact of -rc0 kernel. Lets see if it reappers...
Hmm. So it happens in vanilla 4.4, too... let me see if it happens in v4.6.
Pavel
Signature · 2 lines
(english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html