[Beowulf] MPI performance gain with jumbo frames

[Greg Lindahl]

On Wed, Jun 13, 2007 at 04:30:16PM -0700, laytonjb at charter.net wrote:

> In a multi-core situation,
> do the interrupts affect all of the cores or just one core?

One core gets each interrupt. cat /proc/interrupts to see how this
works in your system.

> I personally like the concept that Level 5 Networks used in conjunction
> with their GigE cards - user space drivers.

This is how everyone does their EtherNot devices: InfiniPath, Myrinet,
Quadrics, yadda yadda.

Then the next question is, why are you bothering with TCP? With
EtherNot, you can avoid all of the interrupts. A typical InfiniPath
system only has a couple of interrupts after running for weeks;
bringing the link up causes a couple. MPI doesn't cause any.

-- greg