hi,
i’m running Debian 10 on POWER9 and would like to spawn x86_64 emulated VMs.
The virtual machine is configured to run with 8 vpus but it’s very slow.
On the host you can see that the qemu-system-x86_64 process is using just one core!
Ppc64le guests are using multi cores, so its looks like an config problem or software bug
with the x86 emulator.
<domain type='qemu'>
<name>ubuntu</name>
<uuid>a38148e3-6a85-4793-8d58-8725e8bef25a</uuid>
<metadata>
<libosinfo:libosinfo
xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0"...
<libosinfo:os
id="http://debian.org/debian/10"/>
</libosinfo:libosinfo>
</metadata>
<memory unit='KiB'>33554432</memory>
<currentMemory unit='KiB'>33554432</currentMemory>
<vcpu placement='static'>8</vcpu>
<os>
<type arch='x86_64' machine='pc-q35-5.0'>hvm</type>
<boot dev='hd'/>
</os>
<features>
<acpi/>
<apic/>
</features>
<cpu mode='custom' match='exact' check='none'>
<model fallback='forbid'>qemu64</model>
</cpu>
<clock offset='utc'>
<timer name='rtc' tickpolicy='catchup'/>
<timer name='pit' tickpolicy='delay'/>
<timer name='hpet' present='no'/>
</clock>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<pm>
<suspend-to-mem enabled='no'/>
<suspend-to-disk enabled='no'/>
</pm>
<devices>
<emulator>/usr/bin/qemu-system-x86_64</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source file='/var/lib/libvirt/images/ubuntu-x86_64.qcow2'/>
<target dev='vda' bus='virtio'/>
<address type='pci' domain='0x0000' bus='0x04'
slot='0x00' function='0x0'/>
</disk>
<disk type='file' device='cdrom'>
<driver name='qemu' type='raw'/>
<target dev='sda' bus='sata'/>
<readonly/>
<address type='drive' controller='0' bus='0'
target='0' unit='0'/>
</disk>
<controller type='usb' index='0' model='qemu-xhci'
ports='15'>
<address type='pci' domain='0x0000' bus='0x02'
slot='0x00' function='0x0'/>
</controller>
<controller type='sata' index='0'>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x1f' function='0x2'/>
</controller>
<controller type='pci' index='0' model='pcie-root'/>
<controller type='virtio-serial' index='0'>
<address type='pci' domain='0x0000' bus='0x03'
slot='0x00' function='0x0'/>
</controller>
<controller type='pci' index='1'
model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='1' port='0x10'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x0' multifunction='on'/>
</controller>
<controller type='pci' index='2'
model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='2' port='0x11'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x1'/>
</controller>
<controller type='pci' index='3'
model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='3' port='0x12'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x2'/>
</controller>
<controller type='pci' index='4'
model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='4' port='0x13'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x3'/>
</controller>
<controller type='pci' index='5'
model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='5' port='0x14'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x4'/>
</controller>
<controller type='pci' index='6'
model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='6' port='0x15'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x5'/>
</controller>
<controller type='pci' index='7'
model='pcie-root-port'>
<model name='pcie-root-port'/>
<target chassis='7' port='0x16'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x02' function='0x6'/>
</controller>
<interface type='bridge'>
<mac address='52:54:00:cc:08:18'/>
<source bridge='br0'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x01'
slot='0x00' function='0x0'/>
</interface>
<serial type='pty'>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
</serial>
<console type='pty'>
<target type='serial' port='0'/>
</console>
<channel type='unix'>
<target type='virtio' name='org.qemu.guest_agent.0'/>
<address type='virtio-serial' controller='0' bus='0'
port='1'/>
</channel>
<input type='tablet' bus='usb'>
<address type='usb' bus='0' port='1'/>
</input>
<input type='mouse' bus='ps2'/>
<input type='keyboard' bus='ps2'/>
<graphics type='vnc' port='-1' autoport='yes'>
<listen type='address'/>
</graphics>
<video>
<model type='qxl' ram='65536' vram='65536'
vgamem='16384' heads='1' primary='yes'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x0'/>
</video>
<memballoon model='virtio'>
<address type='pci' domain='0x0000' bus='0x05'
slot='0x00' function='0x0'/>
</memballoon>
<rng model='virtio'>
<backend model='random'>/dev/urandom</backend>
<address type='pci' domain='0x0000' bus='0x06'
slot='0x00' function='0x0'/>
</rng>
</devices>
</domain>
# ps ax|grep qemu
31546 ? Sl 2:38 /usr/bin/qemu-system-x86_64 -name
guest=ubuntu,debug-threads=on -S -object
secret,id=masterKey0,format=raw,file=/var/lib/libvirt/qemu/domain-59-ubuntu/master-key.aes
-machine pc-q35-5.0,accel=tcg,usb=off,dump-guest-core=off -cpu qemu64 -m 32768 -overcommit
mem-lock=off -smp 8,sockets=8,cores=1,threads=1 -uuid a38148e3-6a85-4793-8d58-8725e8bef25a
-no-user-config -nodefaults -chardev socket,id=charmonitor,fd=32,server,nowait -mon
chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew -no-hpet
-no-reboot -global ICH9-LPC.disable_s3=1 -global ICH9-LPC.disable_s4=1 -boot strict=on
-device pcie-root-port,port=0x10,chassis=1,id=pci.1,bus=pcie.0,multifunction=on,addr=0x2
-device pcie-root-port,port=0x11,chassis=2,id=pci.2,bus=pcie.0,addr=0x2.0x1 -device
pcie-root-port,port=0x12,chassis=3,id=pci.3,bus=pcie.0,addr=0x2.0x2 -device
pcie-root-port,port=0x13,chassis=4,id=pci.4,bus=pcie.0,addr=0x2.0x3 -device
pcie-root-port,port=0x14,chassis=5,id=pci.5,bus=pcie.0,addr=0x2.0x4 -device
pcie-root-port,port=0x15,chassis=6,id=pci.6,bus=pcie.0,addr=0x2.0x5 -device
pcie-root-port,port=0x16,chassis=7,id=pci.7,bus=pcie.0,addr=0x2.0x6 -device
qemu-xhci,p2=15,p3=15,id=usb,bus=pci.2,addr=0x0 -device
virtio-serial-pci,id=virtio-serial0,bus=pci.3,addr=0x0 -blockdev
{"driver":"file","filename":"/var/lib/libvirt/images/ubuntu-x86_64.qcow2","node-name":"libvirt-2-storage","auto-read-only":true,"discard":"unmap"}
-blockdev
{"node-name":"libvirt-2-format","read-only":false,"driver":"qcow2","file":"libvirt-2-storage","backing":null}
-device
virtio-blk-pci,bus=pci.4,addr=0x0,drive=libvirt-2-format,id=virtio-disk0,bootindex=2
-blockdev
{"driver":"file","filename":"/var/lib/libvirt/images/ubuntu-20.04-live-server-amd64.iso","node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}
-blockdev
{"node-name":"libvirt-1-format","read-only":true,"driver":"raw","file":"libvirt-1-storage"}
-device ide-cd,bus=ide.0,drive=libvirt-1-format,id=sata0-0-0,bootindex=1 -netdev
tap,fd=34,id=hostnet0 -device
virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:cc:08:18,bus=pci.1,addr=0x0 -chardev
pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -chardev
socket,id=charchannel0,fd=35,server,nowait -device
virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0
-device usb-tablet,id=input0,bus=usb.0,port=1 -vnc 127.0.0.1:1 -device
qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,max_outputs=1,bus=pcie.0,addr=0x1
-device virtio-balloon-pci,id=balloon0,bus=pci.5,addr=0x0 -object
rng-random,id=objrng0,filename=/dev/urandom -device
virtio-rng-pci,rng=objrng0,id=rng0,bus=pci.6,addr=0x0 -sandbox
on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny -msg
timestamp=on
Does anybody knows this problem?
Best regards
Kim