-1
votes
2answers
198 views

Best type of virtualization when CPU has more threads than cores

I have a 4 cores/8 threads Intel Xeon processor. This is something I tried to particularly ask in SolusVM support, however I haven't got a good reply. I even don't know if they are right: they told me ...
0
votes
1answer
114 views

virt-top says guests are inactive

i was searching a program to show RAM and CPU usage of my KVM guests. I found virt-top which was working yesterday very good. Today i was starting it again and it dont want to work: virt-top 19:46:51 ...
2
votes
2answers
642 views

How to test KVM guest CPU maximum allocation limit?

Running Ubuntu 13.04 Host and vm Guest. Using virtio for hdd, nic. Max-allocaion CPU cores is 6, minimum is 2. here is a screenshot for clarification: http://i.imgur.com/GmYQBMP.png Ive made a vm ...
-1
votes
1answer
301 views

We have Solaris 10 VM in KVM (ProxmoxVE) how to check if Solaris is using all cores?

I'm trying to figure out is VM Solaris 10 (which is virtualized with KVM on ProxmoxVE) using all allocated CPUs? Host HW is Dell poweredge r720. And find a way how to check that for example gzip on ...
-1
votes
1answer
152 views

Kvm poor cpu performance

I have running some Minecraft Servers in a Qemu VM over Libvirt, and the performance is only half good than on real hardware. Libvirt started the vm over: /usr/bin/kvm -S -M pc-1.1 -cpu ...
6
votes
1answer
854 views

KVM/Qemu, Ubuntu: Why do more guests CPUs enhance Disk-I/O rapidly?

We have an Heartbeat/DRBD/Pacemaker/KVM/Qemu/libvirt cluster consisting of two nodes. Each node runs Ubuntu 12.04 64 Bit with the following packages/versions: Kernel 3.2.0-32-generic #51-Ubuntu SMP ...
1
vote
1answer
886 views

How to limit excessive CPU usage from guest OS in KVM

On Xen it is easy as we have CreditScheduler [1], so on a machine with each guest OS sharing only portion of CPU, e.g. 6 guests running on top of a dual core CPU, excessive CPU usage is prohibited. ...
1
vote
1answer
299 views

kvm - cpu cores are disabling and enabling in a loop

On our virtualisation server with KVM, cpu cores are disabling and enabling in a loop after 10 minutes (every disable results in 15 seconds hang for all virtual machines). It happens from ...
12
votes
4answers
19k views

KVM: Which CPU features make VMs run better?

We are using Ubuntu 12.04 with the following parameters: Dell R910 Kernel 3.2.0-25-generic #40-Ubuntu SMP x86_64 x86_64 x86_64 GNU/Linux kvm 1:84+dfsg-0ubuntu16+1.0+noroms+0ubuntu13 qemu-kvm ...
5
votes
2answers
1k views

kvm and qemu host: Is there a limit for max CPUs (Ubuntu 10.04)?

Today we encountered a really strange behaviour on two identical kvm and qemu hosts (Dell R910). The host systems each have 4 x 10 Cores, which means that 40 physical cores are displayed as 80 within ...
1
vote
3answers
598 views

Cgroups vs Tasksets in KVM

I have a CentOS 6 host for several KVM VMs with FreeBSD as guest. I want to bind each VM to use no more than one core at once. What would you suggest to use, Cgroups or Tasksets?
2
votes
2answers
5k views

KVM and virtual to physical CPU mapping

I'm a relative late comer to the virtualistion party, so you'll have to forgive me if this seems like an obvious question. If I have a server with 12 cores available, does each KVM guest have access ...
4
votes
4answers
8k views

Virtualized CPU cores vs. threads

We've got a KVM host system on Ubuntu 9.10 with a newer Quad-core Xeon CPU with hyperthreading. As detailed on Intel's product page, the processor has 4 cores but 8 threads. /proc/cpuinfo and htop ...