OPNsense Forum

Archive => 16.7 Legacy Series => Topic started by: smurfb on June 16, 2016, 11:38:20 am

Title: KVM, high cpu-usage.
Post by: smurfb on June 16, 2016, 11:38:20 am

Since this problem is still present in this latest series I will do another try to see if anyone has the same problem.

Doing a ps aux on my host-machine I get high cpu-usage, the host machine is running Ubuntu 16.04 with a 4.6.2 kernel.

libvirt+  3481  9.1  8.6 2207876 1417684 ?     SLl  jun14 259:22 qemu-system-x86_64 -enable-kvm -name fw -S -machine pc-i440fx-2.5,accel=kvm,usb=off -cpu host -m 1024 -realtime mlock=off -smp 2,sockets=2,cores=1,threads=1

While on the opnsense machine is almost always idle around 0-2% cpu running the latest development build, OPNsense 16.7.b_394-amd64.

Load average   0.16, 0.15, 0.15

Im using pci-passthrough, so no virtual devices for network.

Is anyone else using KVM? Anyone else see this problem?

Title: Re: KVM, high cpu-usage.
Post by: Kev on October 21, 2016, 01:19:47 am

Hi,

I have the exact same issue. Running debian with kvm/libvirt (kernel 4.7 backports) and the host cpu is always around 30-60% when the vm is/should be idle. Host load average is: 0.48, 0.65, 0.95.

I'm using virtio/virtnet. Host CPU is AMD x86_64.

Do you have any ideas or new finding in the meantime?

The only thing I could found are some other reports, indicating that it might be a general freebsd on kvm issue:

https://forum.pfsense.org/index.php?topic=107197.0
https://forum.proxmox.com/threads/high-cpu-idle-usage-with-pfsense-openbsd.19695/

Thanks!