On 02/05/17 15:22, Frediano Ziglio wrote: >> >> >> >> Hi, >> >> I've observed some latency issues, for example, changing focus from one >> terminal to another is a bit sluggish. Typing isn't too bad. >> Interaction with the sliding GNOME unlock screen and drawing the desktop >> after unlock is painfully slow. >> > > Looks like your problems are due to a low bandwidth instead of high > latency. Does spice detect a low bandwidth (should be written in the logs) ? > Can you suggest which log file to check, or journalctl and a possible grep command? >> The virtual server I connect to runs Debian jessie and GNOME 3 desktop, >> it is a default install: >> Xorg = 2:1.16.4-1 >> xserver-xorg-video-qxl = 0.1.1-2+b1 >> spice-vdagent = 0.15.0-1.2 >> >> I'm monitoring the latency of the connection to the KVM/libvirt/SPICE >> server with Smokeping, average ping time is about 0.8ms, no packet loss. >> > > With such network latency you should not have much network latency > issues, unless ssh (which seems you are using add a lot of it) add this > issue. > >> >> I've setup the KVM/libvirt/SPICE host like this: >> Debian stretch >> Kernel = 4.9.13 >> libspice-server1 = 0.12.8-2.1 >> libvirt0 = 3.0.0-3 >> >> >> I've tried using both virt-manager and virt-viewer as clients on a >> Debian jessie system, connecting over SSH to the KVM host, these are the >> client versions: >> >> virt-manager = 1:1.0.1-5 >> virt-viewer = 1.0-1 >> > > Can you try without SSH? > OK, I tried this: virsh edit <domain> and changed the listen IP to 0.0.0.0 Then I used spicy to connect directly to the port as I wasn't sure how to tell virt-manager or virt-viewer to connect directly to the SPICE port. I found some things are a bit faster but it is still not ideal In particular, rendering the gray background of the GNOME unlock screen appears very slow, it renders one line at a time from top to bottom, it takes several seconds. Rendering the desktop background image (default Debian theme) was also slow. I understand that I could change the background image, but the gray lock screen, being a single colour, shouldn't that render more quickly? Unfortunately, before I could test it more, Xorg crashed again, I've submitted the core dump now. >> I noticed it appears a little better with virt-manager than virt-viewer, >> should there be any difference between these two products if they both >> use the same protocol? >> > > Maybe is due to some compression settings difference. Not sure which > compression algorithms are used by virt-manager/virt-viewer. > >> Can I do anything to tweak the .ssh/config to make it better? It >> occurred to me that adding "IPQoS lowdelay" might be useful as it >> defaults to "throughput" for non-interactive connections. Maybe >> virt-manager should add that on the ssh command line? >> > > display requires quite lot of bandwidth, if you set network to > low delay but you use a lot of bandwidth you'll get worst performance. > >> Is there any way to see SPICE latency statistics in the virt-manager GUI? >> >> Would any other SPICE viewer make a difference? >> >> Are there any changes I should make to the GNOME desktop configuration >> to make it work better through SPICE? I've heard people comment on >> changing to fvwm. >> >> Can anybody make any other suggestions? >> >> Regards, >> >> Daniel > > Frediano > _______________________________________________ Spice-devel mailing list Spice-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/spice-devel