I would like to ask you for an explanation what are the "InfiniBand-Stacks". Those were recently changed on our machine and I started running into MPI communication failures. I need some information in order to understand how this might be affecting the stability of my parallel jobs. 

The actual error message I got was : 

> 
> A process failed to create a queue pair. This usually means either the
>  device has run out of queue pairs (too many connections) or there are
>  insufficient resources available to allocate a queue pair (out of
>  memory). The latter can happen if either 1) insufficient memory is
>  available, or 2) no more physical memory can be registered with the
>  device.
> 
> 
> [connect/btl\_openib\_connect\_oob.c:867:rml\_recv\_cb] error in endpoint reply start connect
> 
> 
>