Can't fully utilize CPU

ymmot04

Active Member
May 26, 2011
34
0
26
Chicago, United States
tomfoster.us
I have a 48 core Dell Poweredge R815 (4 chips x 12 cores) and I can't seem to use more than 33% of the CPU with a single VM. I've got a Windows Server 2008 KVM installed and I've been playing with the CPU/core settings and for some reason it seem like each Core I add utilizes 1 physical core. The problem with this is Proxmox has a max of 16 and this server has 48 meaning my VM can only utilize 33% of the CPU. When I run the VM at 100% CPU the node is only running 33%.

Is this a limitation of the software or is something not working right? I was under the impression no matter how many virtual CPUs/Cores you assign the VM it should be able to use 100% of the physical CPU available.

I am using the most recent version of Proxmox.

Has anyone else had this issue?
 
does it work if you enter the values (4 sockets, 12 cores) in the VMID.conf file? (see /etc/qemu-server).

and also post the output of 'pveversion -v'
 
It does not work if I put those values in the configuration file. I tried with 4 sockets, 12 cores, and also 4 sockets, 5 cores. I get this error in the log.

"VM 101 start failed: command '/usr/bin/kvm -monitor unix:/var/run/qemu-server/101.mon,server,nowait -vnc unix:/var/run/qemu-server/101.vnc,password -pidfile /var/run/qemu-server/101.pid -daemonize -usbdevice tablet -name Server2008 -smp sockets=4,cores=5 -nodefaults -boot menu=on -vga cirrus -tdf -localtime -rtc-td-hack -k en-us -drive file=/var/lib/vz/images/101/vm-101-disk-1.raw,if=ide,index=0,cache=none,boot=on -drive file=/var/lib/vz/template/iso/server2008.iso,if=ide,index=2,media=cdrom -m 64000 -netdev type=tap,id=vlan0d0,ifname=tap101i0d0,script=/var/lib/qemu-server/bridge-vlan -device rtl8139,mac=2A:56:D4:36:39:B2,netdev=vlan0d0 -id 101 -cpuunits 1000' failed with exit code 1"

If I reduce it back to 4 sockets, 4 cores it starts fine.

'pveversion -v' returns:

"pve-manager: 1.8-15 (pve-manager/1.8/5754)
running kernel: 2.6.32-4-pve
proxmox-ve-2.6.32: 1.8-32
pve-kernel-2.6.32-4-pve: 2.6.32-32
qemu-server: 1.1-30
pve-firmware: 1.0-11
libpve-storage-perl: 1.0-16
vncterm: 0.9-2
vzctl: 3.0.24-1pve4
vzdump: 1.2-11
vzprocps: 2.0.11-1dso2
vzquota: 3.0.11-1
pve-qemu-kvm: 0.14.0-2
ksm-control-daemon: 1.0-5"
 
This is a fresh install that I am testing on BTW. I also tried updating everything:

"pve-manager: 1.8-17 (pve-manager/1.8/5948)
running kernel: 2.6.32-4-pve
proxmox-ve-2.6.32: 1.8-33
pve-kernel-2.6.32-4-pve: 2.6.32-33
qemu-server: 1.1-30
pve-firmware: 1.0-11
libpve-storage-perl: 1.0-17
vncterm: 0.9-2
vzctl: 3.0.26-1pve4
vzdump: 1.2-12
vzprocps: 2.0.11-2
vzquota: 3.0.11-1
pve-qemu-kvm: 0.14.0-3
ksm-control-daemon: 1.0-5"

Still get this error:

"VM 101 start failed: command '/usr/bin/kvm -monitor unix:/var/run/qemu-server/101.mon,server,nowait -vnc unix:/var/run/qemu-server/101.vnc,password -pidfile /var/run/qemu-server/101.pid -daemonize -usbdevice tablet -name Server2008 -smp sockets=4,cores=5 -nodefaults -boot menu=on -vga cirrus -tdf -localtime -rtc-td-hack -k en-us -drive file=/var/lib/vz/images/101/vm-101-disk-1.raw,if=ide,index=0,cache=none,boot=on -drive file=/var/lib/vz/template/iso/server2008.iso,if=ide,index=2,media=cdrom -m 64000 -netdev type=tap,id=vlan0d0,ifname=tap101i0d0,script=/var/lib/qemu-server/bridge-vlan -device rtl8139,mac=2A:56:D4:36:39:B2,netdev=vlan0d0 -id 101 -cpuunits 1000' failed with exit code 1"
 
Updated to 2.6.35 and now the virtual machine will start with 4 sockets and 12 cores if I manually enter it in the configuration. Thanks for the help guys!

Any idea whether the 16 socket limitation is going to be removed from the gui?
 

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