Anthony Liguori wrote: > Avi Kivity wrote: >> Anthony Liguori wrote: >>> Avi Kivity wrote: >>>> Anthony Liguori wrote: >>>>> It's pretty erratic. If I run if a few times at any rate, >>>>> sometimes I get 0.0 and sometimes I get a more sane result. >>>> >>>> I expect the newer kernel is sometimes disqualifying the timestamp >>>> counter from being used as a clocksource. Running pinned to a cpu >>>> may improve things. >>> >>> Things get better if I disable the PM timer and if I pin to a single >>> CPU. >>> >> >> Can you post the magic command line for future reference? > > I disabled CONFIG_X86_PM_TIMER in the kernel config and then used: > > sudo taskset 1 qemu -hda /dev/volumes/kvm-dev -m 2000 -vnc :3 -kernel > /build/kvm/arch/i386/boot/bzImage -append "root=0301 ro" >
Ah, there's probably a kernel command line to select the clock without resorting to config options. Somebody probably wrote a book about it. > However, this doesn't appear to be a perfect solution. If I launch > the VM redirecting everything to the serial port, I again start having > problems with virtbench. I guess the shear rate of interrupts using > the serial port throws off the accuracy of the clock? I'd have guessed that there wouldn't be many writes to the serial port when testing is in progress. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- 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
