[SOLVED] Build QEMU 2.9 package

[hansm]

I would like to test something and I need to replace pve-qemu-kvm 2.9.0-4 by the original QEMU build (without Proxmox patches). How can I do that? I can download http://download.qemu-project.org/qemu-2.9.0.tar.xz and build it from source but it won't replace the installed pve-qemu-kvm package off course.
Can someone please help me with this? Or point me to documentation about it, if available?

 

[fabian]

you can compile qemu from source without installing and then start your vm using your compiled version ("qm showcmd ID" gives you the generated qemu command line, which you will probably need to adapt a little)

 

[hansm]

Thank you Fabian! I got it working. But the VM is very slow now. The test VM booted within a few seconds and now it takes over 1 minute, also a dd write test in default Proxmox QEMU is approximately 200MB/s and now 40MB/s (I know dd isn't a benchmarking tool, but in the same VM it performs the same normally and I'm not interested in benchmarking atm). Network doesn't work either. Do you have any idea why this is and if it's possible to solve this, I want to compare the 2 as close as possible.

qm showcmd 100:

/usr/bin/kvm -id 100 -chardev 'socket,id=qmp,path=/var/run/qemu-server/100.qmp,server,nowait' -mon 'chardev=qmp,mode=control' -pidfile /var/run/qemu-server/100.pid -daemonize -smbios 'type=1,uuid=bd7f9680-73f0-428e-a421-2e3b6ac733d8' -name test.localdomain -smp '1,sockets=1,cores=8,maxcpus=8' -device 'kvm64-x86_64-cpu,id=cpu2,socket-id=0,core-id=1,thread-id=0' -nodefaults -boot 'menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg' -vga std -vnc unix:/var/run/qemu-server/100.vnc,x509,password -cpu kvm64,+lahf_lm,+sep,+kvm_pv_unhalt,+kvm_pv_eoi,enforce -m 'size=1024,slots=255,maxmem=4194304M' -object 'memory-backend-ram,id=ram-node0,size=1024M' -numa 'node,nodeid=0,cpus=0-7,memdev=ram-node0' -object 'memory-backend-ram,id=mem-dimm0,size=512M' -device 'pc-dimm,id=dimm0,memdev=mem-dimm0,node=0' -object 'memory-backend-ram,id=mem-dimm1,size=512M' -device 'pc-dimm,id=dimm1,memdev=mem-dimm1,node=0' -k en-us -device 'pci-bridge,id=pci.2,chassis_nr=2,bus=pci.0,addr=0x1f' -device 'pci-bridge,id=pci.1,chassis_nr=1,bus=pci.0,addr=0x1e' -device 'piix3-usb-uhci,id=uhci,bus=pci.0,addr=0x1.0x2' -device 'usb-tablet,id=tablet,bus=uhci.0,port=1' -iscsi 'initiator-name=iqn.1993-08.org.debian:01:8bc71019ca99' -drive 'if=none,id=drive-ide2,media=cdrom,aio=threads' -device 'ide-cd,bus=ide.1,unit=0,drive=drive-ide2,id=ide2,bootindex=200' -device 'virtio-scsi-pci,id=scsihw0,bus=pci.0,addr=0x5' -drive 'file=/dev/pve/vm-100-disk-1,if=none,id=drive-scsi0,format=raw,cache=none,aio=native,detect-zeroes=on' -device 'scsi-hd,bus=scsihw0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0,id=scsi0,bootindex=100' -netdev 'type=tap,id=net0,ifname=tap100i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on' -device 'virtio-net-pci,mac=02:74:F2:CE:A1:2D,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300'

Changed to (after compiling QEMU 2.9):

/usr/src/qemu-2.9.0/x86_64-softmmu/qemu-system-x86_64 -chardev 'socket,id=qmp,path=/var/run/qemu-server/100.qmp,server,nowait' -mon 'chardev=qmp,mode=control' -pidfile /var/run/qemu-server/100.pid -daemonize -smbios 'type=1,uuid=bd7f9680-73f0-428e-a421-2e3b6ac733d8' -name test.localdomain -smp '1,sockets=1,cores=8,maxcpus=8' -device 'kvm64-x86_64-cpu,id=cpu2,socket-id=0,core-id=1,thread-id=0' -nodefaults -boot 'menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg' -vga std -vnc unix:/var/run/qemu-server/100.vnc,x509,password -cpu kvm64,+lahf_lm,+sep,+kvm_pv_unhalt,+kvm_pv_eoi,enforce -m 'size=1024,slots=255,maxmem=4194304M' -object 'memory-backend-ram,id=ram-node0,size=1024M' -numa 'node,nodeid=0,cpus=0-7,memdev=ram-node0' -object 'memory-backend-ram,id=mem-dimm0,size=512M' -device 'pc-dimm,id=dimm0,memdev=mem-dimm0,node=0' -object 'memory-backend-ram,id=mem-dimm1,size=512M' -device 'pc-dimm,id=dimm1,memdev=mem-dimm1,node=0' -k en-us -device 'pci-bridge,id=pci.2,chassis_nr=2,bus=pci.0,addr=0x1f' -device 'pci-bridge,id=pci.1,chassis_nr=1,bus=pci.0,addr=0x1e' -device 'piix3-usb-uhci,id=uhci,bus=pci.0,addr=0x1.0x2' -device 'usb-tablet,id=tablet,bus=uhci.0,port=1' -iscsi 'initiator-name=iqn.1993-08.org.debian:01:8bc71019ca99' -drive 'if=none,id=drive-ide2,media=cdrom,aio=threads' -device 'ide-cd,bus=ide.1,unit=0,drive=drive-ide2,id=ide2,bootindex=200' -device 'virtio-scsi-pci,id=scsihw0,bus=pci.0,addr=0x5' -drive 'file=/dev/pve/vm-100-disk-1,if=none,id=drive-scsi0,format=raw,cache=none,aio=native,detect-zeroes=on' -device 'scsi-hd,bus=scsihw0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0,id=scsi0,bootindex=100' -netdev 'type=tap,id=net0,ifname=tap100i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on' -device 'virtio-net-pci,mac=02:74:F2:CE:A1:2D,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300'

The VM is running and I can attach the console from the PVE GUI and stop the VM, read stats, etc.

 

[fabian]

we default to using KVM acceleration, upstream uses tcg by default. you can add '-enable-kvm' to the cmdline, or '-accel kvm'

 

[hansm]

You're fast -enable-kvm works perfectly, thanks!