On 08/15/2011 04:15 PM, Morten Stevens wrote:
The default settings are bad.
Please tell us more about your settings.
In the libvirtd qemu settings I'm using virtio for disk and net. Guests are
Fedora 14+ and SL5/6 using virtio drivers.
I'm using LVM volumes for the disk images, stored on my 8 disk raid10 array.
Had no trouble with exactly the same config in EL5.6.
Otherwise, I recommend the following points:
- controller: virtio
- kvm option: cache=none
- qcow2 disk format with metadata preallocation
- create your disk image with: qemu-img create -f qcow2 -o
size=40000000000,preallocation=metadata vdisk.img
Here's a good link to the topic:
http://www.ilsistemista.net/index.php/virtualization/11-kvm-io-slowness-on-rhel-6.html
Thanks, I'll take a look.
--
Orion Poplawski
Technical Manager 303-415-9701 x222
NWRA/CoRA Division FAX: 303-415-9702
3380 Mitchell Lane [email protected]
Boulder, CO 80301 http://www.cora.nwra.com
