[Beowulf] Performance tuning for Jumbo Frames

[Håkon Bugge]

On Dec 12, 2009, at 7:59 , Rahul Nabar wrote:

> I have seen a considerable performance boost for my codes by using
> Jumbo Frames. But are there any systematic tools or strategies to
> select the optimum MTU size? I have it set as 9000. (Of course, all
> switiching hardware supports jumbo frames and no talking to the
> external world required of the interfaces) Have you guys found
> performance to be MTU sensitive?

Once (i.e. several years ago) I tested an application on Gbe and found  
that around 1/3rd of the MTU was the optimum. But I guess YMMV.

Håkon