tags 574988 + moreinfo thanks Adam Majer wrote: > Package: qemu-kvm > Version: 0.12.3+dfsg-4 > Severity: normal > > I've been using KVM for quite some time now to run Windows XP, 2000, > Vista, and Win 7. Though all the generations of KVM, video speed was > acceptable. After installing qemu-kvm, video display speed inside the > VM has slowed down to below acceptable level. As an example, > > 1. run XP > 2. go to command line > 3. type dir > 4. repeat #3 until window scrolls > > Once the output is scrolling, the speed of redraw has slowed down from > about 1-2s per page (in the kvm-xxx flavours of the package) to > 0.5s/line (in the 0.xx flavours of the package). This is about 10x slower.
I just tried it with 0.12.3+dfsg-4 (the one that entered -testing today). I see almost instant scrolling in winXP and w2k3 cmd window. `dir' in C:\Windows directory takes a few fractions of a second to scroll. I even tried resizing window to full desktop size and changing font to smaller one so that more lines fits in the window (I mean the cmd window inside the guest) - it is still fast, at least I see no visible slowdown compared with native windows. Not even remotely like 1-2s per page or even not 0.5s per PAGE. I tried both -vga std and -vga cirrus (the latter is the default) - to same extent. I can partially confirm that when host and guest _color_ depth does not match (e.g. 16bit color in guest when in host it's 24bit), the mentioned scrolling slows down quite a bit, and becomes at least comparable to 0.5s per PAGE (again, not per LINE). Maybe this is the issue you have? > processor : 0 > vendor_id : AuthenticAMD > cpu family : 15 > model : 75 > model name : AMD Athlon(tm) 64 X2 Dual Core Processor 3800+ One thing I notice is that my CPU is quite a bit faster than this: mine is running at 2.5GHz. So that may explain the difference between your 1-2s/page with my less than 0.5s/page, in case of bad matching of color depth, but the difference is still larger than I'd expect based solely on cpu speed (mine is of the same generation, Athlon x2 64). Note also that since probably kvm-0.11 (kvm-85) the guest window become resizable, and kvm scales the guest image to match the window size. This too requires some processing. In order to be sure there's 1:1 ratio between guest and window size, switch to full-screen mode and back (Hit Ctrl+Alt+F two times). And also, you didn't mention which way you use to see the guest. If you're using sdl window it's one thing, when using vnc console it's entirely different thing. So I'm tagging this as "moreinfo" for now. Thanks! /mjt -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
