WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] [PATCH] Network Checksum Removal

Bin Ren wrote:
I've added the support for ethtools. By turning on and off netfront
checksum offloading, I'm getting the following throughput numbers,
using iperf. Each test was run three times. CPU usages are quite
similar in two cases ('top' output). Looks like checksum computation
is not a major overhead in domU networking.

dom0/1/2 all have 128M memory. dom0 has e1000 tx checksum offloading turned on.

Yeah, if you want to do anything network intensive, 128MB is just
not enough - you really need more memory in your system.


With Tx checksum on:

dom1->dom2: 300Mb/s (dom0 cpu maxed out by software interrupts)
dom1->dom0: 459Mb/s (dom0 cpu 80% in SI, dom1 cpu 20% in SI)
dom1->external: 439Mb/s (over 1Gb/s ethernet) (dom0 cpu 50% in SI,
dom1 60% in SI)

With Tx checksum off:

dom1->dom2: 301Mb/s
dom1->dom0: 454Mb/s
dom1->externel: 437Mb/s (over 1Gb/s ethernet)


iperf is a directional send test, correct?
i.e. is dom1 -> dom0 perf the same as dom0 -> dom1 for you?

thanks,
Nivedita



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