We haven't made the change here, so we're running with the virtio drivers (in Win7 and CentOS64) with <target dev='vda' bus='ide' />. I switched a few VMs over manually to <target dev='vda' bus='virtio' /> (directions are at https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Host_Configuration_and_Guest_Installation_Guide/form-Virtualization_Host_Configuration_and_Guest_Installation_Guide-Para_virtualized_drivers-Using_KVM_para_virtualized_drivers_for_existing_devices.html ) and things seem to work the same.
We'll need to perform some stress-tests to see if the bus='virtio' attribute makes a difference, or if qemu is being smart and adapting to the presence of the driver because of the dev='vda' attribute). Regards, Peter On Fri, Jul 19, 2013 at 10:34 AM, Waldron, Michael H <[email protected]> wrote: > Thanks for the responses on this, I really appreciate it. > > For those that mentioned they actually installed the virtio drivers in their > images for best performance, did you also modify the libvirt.pm module to > define the VM's setting virtio for the disk and network interface types? I > noticed that it's hard-coded to always specify IDE as the disk type and a > default setting on NIC type, rather than specifying virtio. I would assume > these should be set to virtio for the drivers to actually be used. > > > Mike > > Mike Waldron > Systems Specialist > ITS - Research Computing Center > University of North Carolina at Chapel Hill > > ________________________________ > From: Waldron, Michael H > > Sent: Monday, July 08, 2013 3:31 PM > To: [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 >
