On Wed, Jan 20, 2010 at 10:18:06PM -0500, Ryan Pugatch wrote:
Hello all,
I have a PowerEdge 2950 that I am using to host Windows XP VM's under CentOS. I am experiencing poor performance in the Xen VM's. Any time I try to do something, the CPU usage (as reported by the Windows task manager) hits 100% for a few and then drops back down. This is causing the VM's to run sluggish and be quite annoying to use. Example.. I click IE.. cpu hits 100% and IE takes a bit to open. I go to a website.. 100%.. I click a link.. 100%. This is the case even if I only have one VM running.
I now have 32 VM's running on the machine and dom0's cpu usage as reported by xm top is 622%. It seems like Xen is just performing poorly while handling these Windows VMs. Any suggestions? I have Windows VM's on other hardware (typically PowerEdge R905s and R710s and they seem ok).
This 2950 is a decent machine.. 32G RAM, 2x Xeon E5405 (quad core) at 2ghz. And I'm only allocating 1 CPU and 768MB RAM for each VM.
Sample config:
name = "win01n" maxmem = 768 memory = 768 vcpus = 1 builder = "hvm" kernel = "/usr/lib/xen/boot/hvmloader" boot = "c" pae = 1 acpi = 1 apic = 0 localtime = 1 on_poweroff = "destroy" on_reboot = "restart" on_crash = "restart" device_model = "/usr/lib64/xen/bin/qemu-dm" usbdevice = "tablet" sdl = 0 vnc = 1 vncunused = 0 vncdisplay = "1" disk = [ 'file:/var/xen/running/win01n,ioemu:hda,w' ] vif = [ "bridge=xenbr0" ] serial = "pty"
Thanks in advance for any insight!
So I take it you're not using PV-on-HVM drivers in Windows.. ie. windows is using the emulated NIC and IDE disk?
That will be slow.
You need to use PV drivers. See GPLPV drivers: http://wiki.xensource.com/xenwiki/XenWindowsGplPv/ http://www.meadowcourt.org/downloads/
0.11.0.188 is the latest binary release.
-- Pasi