I've been using KVM with Rhel 6.4 and VCL in a test environment and it has been 
completely reliable, as in no crashes or performance degradation thus far. 
However, it has not been heavily loaded yet. On a purely subjective note I've 
been impressed with it - it seems very smooth. I haven't tried much in the way 
of image conversion. I did find getting to grips with 
virt-install/virt-manager/virsh/qemu etc rather confusing at first but it 
becomes much clearer with use.

VCL has had no issues with a lot of configuration changes on the Host (I've 
completely changed the VM working directory a couple of times), as long as the 
'VM Host Profiles' information is correct it copes with it just fine.

From: Dmitri Chebotarov [mailto:[email protected]]
Sent: Monday, July 08, 2013 4:15 PM
To: [email protected]
Subject: RE: VMware vs. KVM on VCL

Hi Mike

I've been using VMWARE and KVM in the same VCL environment for little over a 
month.

While VCL can convert from VMDK to QCOW2 I choose to have dedicated KVM images 
in qcow2 format. The main reason for it is to have virtio drivers installed in 
VM for better OS performance. Also I couldn't get the KVM->VMWARE conversion to 
work - qemu-img creates image which ESXi doesn't recognize.

I'm using RedHat 6.3/4 as KVM host OS. Also tried CentOS 6.3/4 before. This 
could be related to hardware I have (IBM HS22 blades), but RedHat runs better 
in my case. I've experienced unexpected reboots with CentOS. I haven't tried 
Fedora in production.

KVM works very well so far. Looks like it creates/loads VMs faster on the same 
hardware/storage compared to ESXi 4.1. I haven't had any KVM related issues 
with VCL.

I hope it helps.

Thanks.

________________________________
From: Waldron, Michael H [[email protected]]
Sent: Monday, July 08, 2013 3:31 PM
To: [email protected]<mailto:[email protected]>
Subject: VMware vs. KVM on VCL
I'm curious to hear about people's experiences/opinions with VMware and KVM on 
VCL. Up to this point, we have been using the free version of VMware ESXi, but 
I've done some testing with KVM, and it seems to work well also.

It looks like the two will co-exist well, as KVM successfully converts the vmdk 
images to qcow2 format on the fly, and will even convert new images created on 
KVM back to vmdk format if the repository is defined as vmdk format.

So I'm toying with the idea of migrating away from VMware and going to KVM, and 
wanted to hear about others experiences if they've done the same, or can 
compare performance between the two hypervisors. Also, if you are using KVM, 
what OS are you running it on. The testing I did was with KVM running on Fedora 
16.

Thanks,
Mike

Mike Waldron
Systems Specialist
ITS - Research Computing Center
University of North Carolina at Chapel Hill

Reply via email to