[Beowulf] mpi slow pairs

[Michael Di Domenico]

On Fri, Aug 29, 2014 at 11:38 AM, John Hearns <John.Hearns at viglen.co.uk> wrote:
>> Also have you run  ibdiagnet to see if anything is flagged up?
>
> i've run a multitude of ib diags on the machines, but nothing is popping out as wrong.  what's weird is that it's only certain pairing of machines not any one machine in general.
>
> Would that then be a problem in one of the blades or a part of the switch?

not sure yet, i think on the spine modules in the switch is silently
failing to send traffic a full speed, but i've not been able to
"prove" this yet.