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