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

Re: [Xen-users] Very slow domU network performance





Winston Chang wrote:
On Apr 4, 2006, at 1:59 PM, Stephen C. Tweedie wrote:

The packet loss is as follows:
domU --> domU  0% (using 127.0.0.1)
domU --> domU  0% (using domU eth0 IP address)
dom0 --> domU  ~100% (only 7 of 38464 made it!)

Yow.

There have been a number of weird checksum problems identified in the
past with Xen's networking; a checkin was just made a day or two ago
which cleans up the checksum handling in a way which may well help here.
We'll have to see whether an updated dom0/domU kernel improves things
much.

I ran the test with the latest xen-unstable build. The results are the same.

When I ran 'xm sched-sedf 0 0 0 0 1 1' to prevent domU CPU starvation, network performance was good. The numbers in this case are the same as in my other message where I detail the results using the week-old xen build -- it could handle 90Mb/s with no datagram loss. So it looks like the checksum patches had no effect on this phenomenon; the only thing that mattered was the scheduling.


What was the previous weight of domain 0? What is the weight assigned to the domU's and do the domU's have bursting enabled?

Thank you,
Matt Ayres

_______________________________________________
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®.