>>> On Sun, May 13, 2007 at 10:06 AM, in message <[EMAIL PROTECTED]>, "Dor Laor" <[EMAIL PROTECTED]> wrote: >> > >>> Superb results, when I run the old in- kernel apic I got much higher > idle >>> cpu consumtion. I know that's vmenter- vmexit latency was drastically >>> improved but 0- 1% cpu consumption for winxp 32 bit sounds too good > to be >>> true. >>> Are you sure an ACPI HAL is used in the guest? (can be checked by >>> looking at the computer node in the device manager). >> >>I did a clean install and didn't change it over to StandardPC. The > Control >>Panel says "ACPI Uniprocessor PC" or something like that (recalling > from >>memory right now). As a third datapoint, I am seeing the TPR changing >>rapidly (which I would expect 0 changes if the ACPI stuff was > disabled). > > Great, I was a little skeptical (sorry for that)
No problem. > since several months > ago when I tested the in- kernel- apic the idle time was much worse. After > talking today with Avi, he said his vmentry- exit latency drastically > improved performance and even the qemu's apic can reach these figures. Yeah. At first I was psyched when I saw my code running at 0-1%, but then I ran trunk and saw its not all that different :( The good news is that windows is performing pretty well now, regardless of my patch or not. Thats good for KVM all around. > I'm sure that with load, you implementation will achieve performance > advantage. In theory, we should be able to take advantage of all the light-exit gains we have made recently since that is the primary difference for windows+ACPI now. This means the APIC change will have an increasing impact as we improve the VMEXIT times (both in HW and SW). So even if it doesn't make a huge diff today, it will always be contributing more and more as we push the ball forward in other areas. But I am not disappointed. My primary motivation is functionality, not performance. ;) I need to be able to inject interrupts to a guest from the kernel for the work I am doing. If I also improve performance, great! ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
