On Fri, Dec 11, 2009 at 08:09:36PM -0600, Reuben Martin wrote: > On Fri, Dec 11, 2009 at 9:18 AM, torbenh <torbenh@xxxxxx> wrote: > > On Mon, Dec 07, 2009 at 01:48:04AM -0600, Reuben Martin wrote: > >> On Sun, Dec 6, 2009 at 4:14 AM, Patrick Shirkey > >> <pshirkey@xxxxxxxxxxxxxxxxx> wrote: > >> > > >> > On 12/06/2009 03:20 PM, Reuben Martin wrote: > >> >> On Sat, Dec 5, 2009 at 8:39 PM, Paul Davis<paul@xxxxxxxxxxxxxxxxxxxxx> wrote: > >> >> > >> >>> On Sat, Dec 5, 2009 at 2:51 PM, Reuben Martin<reuben.m@xxxxxxxxx> wrote: > >> >>> > >> >>>> Does anybody know if it is possible to run a guest OS under KVM and > >> >>>> have the ins and outs of the virtual audio device presented to that > >> >>>> OS, interface with JACK on the host linux system? > >> >>>> > >> >>>> I've done a little googling on this but couldn't find anything. > >> >>>> (mostly because "jack" is ambiguous, and "KVM" can mean a lot of > >> >>>> things) > >> >>>> > >> >>> unless the VM software that provides fake audio devices to the guest > >> >>> OS knows about JACK internally or can be configured to use it, this is > >> >>> not happening. > >> >>> on the other hand, if the VM software can simply use the ALSA JACK > >> >>> plugin, that could potentially work (lots and lots of latency though). > >> >>> > >> >>> > >> >> In that case I guess my best bet would probably be to petition KVM > >> >> development to add support for JACK. Currently I believe it supports > >> >> ALSA, OSS, SDL and PulseAudio. > >> >> > >> >> > >> > > >> > If KVM already supports those api's then it can be used with jack via > >> > several different methods. What is the problem that you are having exactly? > >> > > >> > >> No problems yet. I'm putting together a new system and had thought of > >> using Windows and Mac as guest VM systems under KVM for running things > >> that don't exist for Linux and/or don't work well with WINE. And I > >> wanted to see if anybody had tried routing the VM audio ins / outs to > >> JACK rather than directly to an audio sink. > >> > >> Wanted to see if anybody had seriously tried this before I gave it a go. > > > > using netjack and the master running at -p1024 seems to be working fine. > > at least when i compress the audio, and there is not too much gfx memory > > transfers. > > > > i have put a windows build of jacknone-0.4 on http://netjack.sf.net > > this is basically jack-1.9.4 with qjackctl and a fixed audioadapter. > > it includes netone with celt-0.7 and jack_trans2midi which generates > > midi clock... so you can sync your windows apps to jack transport. > > > > > > -- > > torben Hohn > > > > Very nice. The part about having an ASIO based netjack interface is a > key element that I was not aware existed. And the jack-midi virtual > device solves the transport issue as well. I need to give this a try > once I finish building my new system. > > I'll also be interested to see how well routing netjack connections > between a windows guest and mac guest works out. Should be > interesting. > > Perhaps in cases like this where more than one jack process is > competing for processor time, Round Robin scheduling might work > better... only if you were using zero-latency mode. but i dont think you can use that with a VM. netjack lowers the scheduling requirements of the slave a bit. > > I'm interested to see how KVM compares to VirtualBox. From what I > understand it's a bit faster / lower latency because it "runs closer > to the metal" compared to VirtualBox / Xen / VMware. yup. me too. can it run win7 yet ? i dont have a real choice, because win7 is the only OS, MS gave out for free. the basic problem with VMs is that they seem to have a single thread emulating the hardware, so if a big gfx operation is in progress, the network processing will get deferred. (at least in VirtualBox) maybe this doesnt happen with the VM audio. -- torben Hohn _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user
