[Xen-users] Re: GPLPV drivers problem

[dil <penne296@xxxxxxx>]

James Harper <james.harper <at> bendigoit.com.au> writes:

> 
> > 
> > I run iperf as a client on the domu and as a server on the dom0.
> > 
> > i also tried an ftp transfer ( ftp server on the dom0) ( lvm lv as
> volumes
> > to get better disk performances )
> > 
> > the transfer rate was 140Mb/s max ( second run ) but the cpu was 100%
> > loaded (60% for ftp.exe and 30 % system )
> > 
> > it seems that the high cpu load during network utilization is the main
> > limiting factor.
> > 
> > i disabled ms/qos with no luck
> 
> I have been tinkering with patching the windows kernel to remove a
> particularly inefficient instruction, based on Travis Betak's amdvopt
> driver (on sourceforge).
> 
> That driver by itself should make XP fly on AMD processors. I am working
> on putting it into the xenpci driver, which I've done, and then making a
> similar optimization for Intel processors.
> 
> A test I just did got the XP throughput going from 35 MBits/second to
> 350 MBits/second. Once I have sorted out a licensing issue with Travis
> and done some port testing I'll release the updated GPLPV drivers.
> 
> Windows 2003 sp2 included a similar fix built into the kernel, so you
> won't see any performance increase there. Windows 2008 and Vista have
> the same thing already too.
> 
> James
> 

Thanks for the tip ...

i installed the amdvopt driver and an iperf test gave a throughput of 440Mb/s

with two vcpus.

with one vcpu the results are lower.

i also got good results for an ftp test between the doms.

Cpu usage is still high but much lower than before.


if i disable "checksum on rx packets" on the xen adapter iperf jumps to 725Mb/s

_impressive_ !!!!


i tried to add a second iperf thread ( -P2 option ) and got 436 Mb/s

Thanks a lot for your help

Mike






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