Ralf <[email protected]> wrote: > Hi out there, > > assume the following situation: > > I do have a minimalistic hypervisor running a minimalistic virtual > machine (qemu with kvm, qxl and spice). > Both systems, hypervisor and VM are able to run X servers and > apllications. The graphics card of the hypervisor is connected to a > monitor. This monitor only has to show one single standalone QT > application which is running on the virtual machine. > > What will give me more video performance? > > 1. Running a minimalistic X server on the virtual machine showing the > application AND running a minimalistic X server on the hypervisor > running remote-viewer > or > 2. Running a minimalistic X server on the hypervisor and using > X11-Forwarding via bridged ethernet > > Or maybe even someone knows a better solution? > > Thank you folks! > > Cheers > Ralf
On my system, qemu-kvm has the best performance with X11 on guest. I've also tested vnc and spice with qxl video driver on guest, but X11 was faster. I can imagine that this depends on the hardware and screen resolution. So maybe on your system an other setup is better. My host GPU is a Radeon Ultimate R7 250, resolution is 3840x2160@60Hz, driver is xf86-video-ati. X11 compositing is deactivated on host as well as on guest. As "video card" on guest I use vmware (-vga vmware). Screen resolution on guest is 2386x1770. That seems to be the highest possible screen size that is available with this settings. I also tested other guest video drivers (std and cirrus) but vmware was the fastest and also the one with the highest resolution. Before I bought an UHD monitor, I used sdl as qemu display (-display sdl) in borderless fullscreen mode (-no-frame -full-screen). I used the same screen resolution on host and guest (1920x1200) and qemu was running on one of my virtual XFCE desktops. This was very handy. But as I've written before, it seems not possible for me to run qemu with UHD screen size. So fullscreen mode isn't possible any longer and now qemu runs in a window on my desktop (-display gtk). But with none of my setups it was/is possible to run a fullscreen video on the guest vm. Performance is much to slow for that. I've spent some time to make it faster, but I failed. I would be happy for any hints about better video performance with qemu. -- Regards wabe
