On Fri, May 26, 2023 at 09:11:57AM +0200, br...@mailbox.org wrote: > >Synopsis: OpenBSD in QEMU KVM: High QEMU CPU usage when OpenBSD is 100% > >idle > >Category: kernel > >Environment: > System : OpenBSD 7.3 > Details : OpenBSD 7.3 (GENERIC.MP) #1125: Sat Mar 25 10:36:29 MDT > 2023 > > dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP > > Architecture: OpenBSD.amd64 > Machine : amd64 > >Description: > I installed OpenBSD 7.3 inside a QEMU QCOW2 disk with QEMU > running on Linux. I ran `top -S` in the VM and idle is at 100%. > So I expect CPU usage of the host QEMU process to be 0%, instead > it ranges from 4% to 6%. I tried other VMs with the same QEMU > settings but running Linux and FreeBSD, in both cases the QEMU > process stays infact at 0% usage. I attach `vmstat -i` as was > suggested on IRC. Not sure if relevant but on FreeBSD the Total > rate given by the same command is around 50. > > >How-To-Repeat: > This is the QEMU args used to run the VM: > > qemu-system-x86_64 -enable-kvm -cpu host -smp 16 -m 2048 > -nodefaults \ -drive if=virtio,format=qcow2,file=openbsd.qcow2 > -nic user,model=virtio-net-pci,id=net0 -display curses -vga std > > > vmstat -i: > interrupt total rate > irq114/virtio0 10245 0 > irq98/virtio1 29136 2 > irq100/fdc0 1 0 > irq144/pckbc0 14 0 > irq0/clock 33566752 3177 > irq0/ipi 164241 15 > Total 33770389 3196
perf top on the linux side to see where qemu is spending it's time?
