RE: [PATCH rdma-core] iwpmd: Return existing mapping if port reused on active side

Steve Wise
2017-10-10T20:19:51Z

> >
> > How is a new connection re-using the local port exactly? Is there a test
case
> > that reproduces this?
> >
> > Other than that,
> >
> > Reviewed-by: Steve Wise <swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
> >
>
> Hi Steve,
>
> A new connection can reuse a local port if one of destination port,
destination
> address
> or source address differs from an existing connection.
>
> This optimization for port reuse was added in kernel in
> commit 19b752a19dce ("IB/cma: Allow port reuse for rdma_id")
>
> https://patchwork.kernel.org/patch/9499071/
>
> We saw the port-mapper "duplicate mapping error" during Open MPI scale up
> testing.

Ah, I see now. Thanks!

Steve.