[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-users] GPLPV drivers problem




On Jan 6, 2009, at 12:15 AM, James Harper wrote:


Hello.
I've been using Xen with some virtual machines for at least 2 years
now. When we all gone to VT-X, the xen world was introduced to windows
and we all enjoyed that... until we realized we needed drivers for it
to work =) We need to thank to James Harper for his efforts in making
the GPL PV drivers, so thanks!

Thanks


Today I installed 0.9.12-pre13 to test the performance - again the
performance is very similar with or without the pv drivers (screenshot
of device manager: http://uplink.lvengine.com/device.jpg )
I've benchmarked the network with iperf between Xen virtual machines
(pv machines, not hvm) and I get 2.5gbps ~ 3.0gbps, but with windows I
get around 40mb/s. My kernel times are almost 100% all the time and
disk performance is relatively slow (benchmarked with some windows
app, hd_speed, got me around 11mb/s - not bad, but the kernel times
are always up there... see http://uplink.lvengine.com/disk.jpg for a
screenshot).

I use Xen 3.2.1, on a gentoo linux, so xen is compiled from source
(for gentoo people, I have ioemu and pygrub use flags). I'm using
kernel 2.6.21 - I think this patchset was made by Red Hat, and
recently gentoo masked this version (or the version was already
masked), but i needed to use the .21 kernel because .18 doesn't have
support for one of my nic's and for the sata driver I think.

<snip>

I've tried using ioemu: in the "hda" device and it's the same. I've
removed the /gplpv entry from boot.ini as -pre13 doesn't need it
anymore.
I must be configuring something wrong, maybe it's the ACPI
Multiprocessor PC kernel? (I installed this system a long time ago,
before the PV drivers - changing the acpi setting now could be bad...
- but if it must, I can try changing it...)
Something odd is that cpu-z reports to me that the cpu has only
812mhz, but windows detects it's a 2.24ghz processor (single
processor, i know the drivers have problems with smp and I don't need
smp anyway)

I basically only run SQL server in this machine, and for a machine
with 1.5gb of memory it runs really slow :/


What OS are you using? If it's 2003 then make sure sp2 is installed.

I'm using windows XP SP2 (sp2 on purpose).
I have a Intel Core2 duo 2133mhz, 4mb cache with VT-X enabled.

I have the firewall disabled, but you said in another mail to disable the service. I did and it boosted performance to 100mbits. Still slow though :/



Switching to the 'Standard PC' hal is easy enough. Switching back is a bit of a pain but you could just try it on an lvm snapshot.


should I be using the standard pc configuration or the acpi one?

James



I have a spare 50gb partition on my lvm and sometime ago I made a copy of the windows partition. I have a windows system with a almost exact copy now. I'll try installing the -pre13 drivers and switching HAL configurations just to test if it works better.

I can only have windows XP because that's the license that I have for that computer ....

Luis

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.