Another interesting thing: on guest side, when i leave the screen quiet, for example just showing desktop with no animations at all (so there's no change in what should be drawed) things improve a lot of, and then i coudl hear a song perfectly. The screen is 1680x1050. the same thing happens when i low screen resolution to 800x600
Could be the emulated VGA graphic adapter latency? I suppose that i haven't 2D acceleration so CPU has to paint the screen everytime a change is done. On Thu, Feb 11, 2010 at 7:07 PM, Alberich de megres <alberich...@gmail.com> wrote: > On Thu, Feb 11, 2010 at 8:42 AM, malc <av1...@comtv.ru> wrote: >> On Thu, 11 Feb 2010, Alberich de megres wrote: >> >>> On Thu, Feb 11, 2010 at 7:53 AM, malc <av1...@comtv.ru> wrote: >>> > On Thu, 11 Feb 2010, Alberich de megres wrote: >>> > >>> >> I'm using the alsa driver. >>> >> Even I tried to change some values using the export and some flags >>> >> that -audio-help shows, but nothing significant. >>> > >>> > Please do not top post. >>> >>> Sorrry!! >>> >>> > >>> >> >>> >> >>> >> On Thu, Feb 11, 2010 at 1:03 AM, malc <av1...@comtv.ru> wrote: >>> >> > On Thu, 11 Feb 2010, Alberich de megres wrote: >>> >> > >>> >> >> Hi! >>> >> >> >>> >> >> I'm running qemu on suse, and i got a very high audio latency. For >>> >> >> example, using windows latency is about 4s and audio gets distorted >>> >> >> with little cuts. >>> > >>> > How do you measure it? >>> With a program called dpc latency, it's for windows. >>> >>> > >>> >> >> On the host side (suse), i changed the audio pci device latency to 99 >>> >> >> but this only improves a little bit. >>> > >>> > As in: with setpci? >>> Yes. I also tired, on host, to low latency to VGA to 10. >> >> That's completely unrelated latency [1] >> >>> > >>> >> >> Other thing i noticed is when lowering video resolution, the audio >>> >> >> latency gets better and better. >>> > >>> > Lowering video resolution of what? Guest, host? >>> >>> Yes, it was on guest. Even for example if i change the desktop or >>> switch to a text terminal when things works better what suggested me >>> that could be something with painting the screen. But i'm not shure if >>> its just only a side effect of a bad launch command, or something >>> else. >>> >>> > >>> >> >> I started played with source code, but i'm just a newbie on qemu. >>> >> >> Anyone can point some light to me please? >>> >> >> >>> >> >> thanks guys!! >>> >> > >>> >> > -audio-help is your friend, from there you can deduce (at the very >>> >> > least) >>> >> > which audio driver your qemu uses. >>> >> > >>> > >>> > It would also help to know which version of QEMU you run and exactly how >>> > you invoke it. >>> >>> You're right..sorry: >>> >>> qemu-kvm -cpu core2duo -smp 2 -m 1024 -hda /home/nine/imgs/hda1.img >>> -vga std -usbdevice tablet >>> -name t1 -net nic,macaddr=55:54:00:12:34:56 -net >>> tap,ifname=tap1,script=no >>> -soundhw ac97 >> >> I can't help you with kvm and windows, that said here are the things >> to try: >> a. Vanilla qemu >> b. No smp >> > The same thing. > When playing sounds, i get little cuts. > > >> And i'm not saying that those will help, just trying to collect more >> data points. >> >> P.S. 4 seconds of latency is sortof insane, especially given that >> default buffering for ALSA is nowhere near that, not by a >> longest shot. >> >> [1] http://www.reric.net/linux/pci_latency.html >> >> -- >> mailto:av1...@comtv.ru >> >
