ksoftirqd/0 high cpu usage

[robhost]

Hi,

we've got a problem with one of our proxmox nodes. ksoftirqd/0 eats here sometimes 100% CPU on Core 0 (system has dual xeon E5-2620v2, 256 GB RAM, RAID6) and network is then slow /w packet loss.

We already bootet with kernel options nohz=off and pcie_aspm=off but it did not help. Overall load on the system is ~2.0 - 3.0, so this should not be the problem here.

The machine runs latest PVE with latest kernel:

proxmox-ve-2.6.32: 3.2-126 (running kernel: 2.6.32-29-pve)pve-manager: 3.2-4 (running version: 3.2-4/e24a91c1)
pve-kernel-2.6.32-27-pve: 2.6.32-121
pve-kernel-2.6.32-29-pve: 2.6.32-126
pve-kernel-2.6.32-26-pve: 2.6.32-114
pve-kernel-2.6.32-23-pve: 2.6.32-109
lvm2: 2.02.98-pve4
clvm: 2.02.98-pve4
corosync-pve: 1.4.5-1
openais-pve: 1.1.4-3
libqb0: 0.11.1-2
redhat-cluster-pve: 3.2.0-2
resource-agents-pve: 3.9.2-4
fence-agents-pve: 4.0.5-1
pve-cluster: 3.0-12
qemu-server: 3.1-16
pve-firmware: 1.1-3
libpve-common-perl: 3.0-18
libpve-access-control: 3.0-11
libpve-storage-perl: 3.0-19
pve-libspice-server1: 0.12.4-3
vncterm: 1.1-6
vzctl: 4.0-1pve5
vzprocps: 2.0.11-2
vzquota: 3.1-2
pve-qemu-kvm: 1.7-8
ksm-control-daemon: 1.1-1
glusterfs-client: 3.4.2-1

Is there a problem with the interrups or something? Help or any hint would be appreciated - thanks!

 

[masterdead]

have you installed irqbalance?

ps uax|grep irqbalance

install from https://packages.debian.org/wheezy-backports/irqbalance

More info in /proc/interupts

 

[robhost]

have you installed irqbalance?

install from https://packages.debian.org/wheezy-backports/irqbalance

More info in /proc/interupts

Thanks - didnt notice that this is not within the standard installation of Proxmox. I think they should add it to the default packages asap
The packet loss is gone for now, irqbalance helped a lot here.

But ksoftirqd/0 is still there sometimes and eats cpu time, even if the box has not a high loadavg.