Re: New MPI benchmark performance results (update)

[Nivedita Singhvi <niv@us.ibm.com>]

xuehai zhang wrote:
> Hi all,
> 
> In the following post I sent in early April 
> (http://lists.xensource.com/archives/html/xen-devel/2005-04/msg00091.html), 

Hi, thanks for sharing the data - it was interesting.
I tried to find additional data on the benchmarks using
the link you have for the user manual but it gave me
a 404 Error. It wasn't clear whether your benchmarks
use TCP or UDP or possibly raw sockets?

As has been pointed out by several people, running the
2.6 kernel and comparing apples to apples as much as possible
would help.

Is there any chance you kept some of the system statistics
and settings (netstat -s, sysctl -a info)?.
Did you tune the settings for the system at all?

> Alltoall latency (max domU/linux > 60). The performance difference in 
> the last example is HUGE and we could not think about a reasonable 
> explaination why transferring 512B message size is so much different 
> than other sizes. We appreciate if you can provide your insight to such 
> a big performance problem in these benchmarks.

You have an anomalous point on most of the results - and again,
knowing what kind of traffic this is would really help.

thanks,
Nivedita