Re: XP smp using a lot of CPU

[Ross Boylan <ross@biostat.ucsf.edu>]

On Wed, 2009-05-13 at 09:56 +0300, Avi Kivity wrote:
> Ross Boylan wrote:
> > I just installed XP into a new VM, specifying -smp 2 for the machine.
> > According to top, it's using nearly 200% of a cpu even when I'm not
> > doing anything.
> >
> > Is this real CPU useage, or just a reporting problem (just as my disk
> > image is big according to ls, but isn't really)?
> >
> > If it's real, is there anything I can do about it?
> >
> > kvm 0.7.2 on Debian Lenny (but 2.6.29 kernel), amd64.  Xeon chips; 32
> > bit version of XP pro installed, now fully patched (including the
> > Windows Genuine Advantage stuff, though I cancelled it when it wanted to
> > run).  
> >
> > Task manager in XP shows virtually no CPU useage.
> >
> > Please cc me on responses.
> >
> >   
> 
> I'm guessing Windows uses a pio port to sleep, which kvm doesn't 
> support.  Can you provide kvm_stat output?
markov:~# kvm_stat -1
efer_reload                    0         0
exits                    9921384       566
fpu_reload                267970         0
halt_exits                     1         0
halt_wakeup                    3         0
host_state_reload        4026050        17
hypercalls                     0         0
insn_emulation           1329455         0
insn_emulation_fail          154         0
invlpg                    176773         0
io_exits                 3818270         0
irq_exits                1434046       566
irq_injections            326730         0
irq_window                164827         0
largepages                     0         0
mmio_exits                 35892         0
mmu_cache_miss             29760         0
mmu_flooded                19908         0
mmu_pde_zapped             15557         0
mmu_pte_updated            82088         0
mmu_pte_write              97990         0
mmu_recycled                   0         0
mmu_shadow_zapped          43276         0
mmu_unsync                   891         0
mmu_unsync_global              0         0
nmi_injections                 0         0
nmi_window                     0         0
pf_fixed                 1231164         0
pf_guest                  276083         0
remote_tlb_flush          115606         0
request_irq                    0         0
request_nmi                    0         0
signal_exits                   5         0
tlb_flush                 960198         0

This is with the VM displaying the XP "It is now safe to turn off your
computer".  CPU remains about 200% from kvm.  Invoked with
sudo vdeq kvm -net nic,vlan=1,macaddr=52:54:a0:12:01:00 \
    -net vde,vlan=1,sock=/var/run/vde2/tap0.ctl \
    -std-vga -hda XP.raw \
    -boot c \
    -soundhw es1370 -localtime -no-acpi  -m 1G -smp 2

Next I'll trying fiddling with acpi.

-- 
Ross Boylan                                      wk:  (415) 514-8146
185 Berry St #5700                               ross@biostat.ucsf.edu
Dept of Epidemiology and Biostatistics           fax: (415) 514-8150
University of California, San Francisco
San Francisco, CA 94107-1739                     hm:  (415) 550-1062