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 >