Load Issue with Cloud Linux running in KVM virtual machine

[support]

KVM snapshot backup

[eric.merkel]

I have a Cloud Linux server running inside a KVM virtual machine on proxmox 3.3 hypervisor. This is the first CL server we have run on this platform. We have many other Centos 6 and Windows Server 2008/2012 etc. The CL server runs fine is most instances. As soon as we do a VM snapshot backup which is using an underlying LVM backed storage to an NFS server, we start seeing a high load on the CL server. It looks like the system is simply waiting on IO and gets sluggish and sometimes causes SMTP/HTTP processes to timeout.

uname -a

Linux 2.6.32-531.29.2.lve1.3.11.1.el6.x86_64 #1 SMP Thu Dec 18 06:49:17 EST 2014 x86_64 x86_64 x86_64 GNU/Linu

cat /etc/redhat-release

CloudLinux Server release 6.6 (Leonid Kizim)

Am I running the proper kernel? This is really unexpected because the VM should have no idea that the underlying hypervisor is taking a backup and it should be minimal IO for the hypervisor. We do not see these load issues on regular Centos or Windows systems or more highly loaded hypervisors.

I am looking for ideas and suggestions.

Best regards,
Eric