Hi, Are you running ntp in the host or timekeeping in the guest? If so, is the guest clock close to what current time should be?
Also, can you try adding this option: -global mc146818rtc.lost_tick_policy=slew -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1318830 Title: High CPU usage on windows virtual machine Status in QEMU: New Status in qemu package in Ubuntu: New Bug description: I got Ubuntu 14.04, with Qemu 2.0 and moved my windows VM to this new box, and made sure that what this article indicates was achieved https://www.kraxel.org/blog/2014/03/qemu-and-usb-tablet-cpu-consumtion/ I can attest that it works following the instructions, erasing the registry, etc. Unfortunately, with 4 cpus as below, I still see 60% CPU outside as shown by "Top" versus 0% CPU inside. My Kernel is 3.15.0-031500rc4-generic If some developer wants to log in and take a look, I am happy to help. The box is not in production and I take full responsibility. Until this is solved, KVM is not going to compete with Hyper-V or Vmware. Basically KVM is not suitable for the Enterprise as of yet. qemu-system-x86_64 -enable-kvm -name Production -S -machine pc- i440fx-2.0,accel=kvm,usb=off -cpu kvm64,+rdtscp,+pdpe1gb,+x2apic,+dca,+pcid,+pdcm,+xtpr,+tm2,+est,+smx,+vmx,+ds_cpl,+monitor,+dtes64,+pclmuldq,+pbe,+tm,+ht,+ss,+acpi,+ds,+vme,hv_relaxed,hv_vapic,hv_spinlocks=0xfff -m 4024 -realtime mlock=off -smp 4,sockets=1,cores=4,threads=1 -uuid e8701c5c-b542-0199-fd2a-1047df24770e -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/Production.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=localtime -no-shutdown -boot strict=on -device piix3-usb- uhci,id=usb,bus=pci.0,addr=0x1.0x2 -drive file=/var/lib/libvirt/images/Production.img,if=none,id=drive-virtio- disk0,format=raw -device virtio-blk- pci,scsi=off,bus=pci.0,addr=0x6,drive=drive-virtio-disk0,id=virtio- disk0,bootindex=1 -netdev tap,fd=30,id=hostnet0,vhost=on,vhostfd=31 -device virtio-net- pci,netdev=hostnet0,id=net0,mac=00:16:3a:d2:cd:ea,bus=pci.0,addr=0x3 -netdev tap,fd=35,id=hostnet1,vhost=on,vhostfd=36 -device virtio-net- pci,netdev=hostnet1,id=net1,mac=52:54:00:70:fe:54,bus=pci.0,addr=0x4 -chardev pty,id=charserial0 -device isa- serial,chardev=charserial0,id=serial0 -device usb-tablet,id=input0 -vnc 127.0.0.1:0 -device VGA,id=video0,bus=pci.0,addr=0x2 -device intel-hda,id=sound0,bus=pci.0,addr=0x5 -device hda- duplex,id=sound0-codec0,bus=sound0.0,cad=0 -device virtio-balloon- pci,id=balloon0,bus=pci.0,addr=0x7 To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1318830/+subscriptions