Re: [PATCH] RDMA/ipoib: distribute cq completion vector better

Jason Gunthorpe
2020-10-29T00:22:33Z

On Tue, Oct 13, 2020 at 09:43:42AM +0200, Jack Wang wrote:
> Currently ipoib choose cq completion vector based on port number,
> when HCA only have one port, all the interface recv queue completion
> are bind to cq completion vector 0.
>
> To better distribute the load, use same method as __ib_alloc_cq_any
> to choose completion vector, with the change, each interface now use
> different completion vectors.
>
> Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
> Reviewed-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
> ---
> drivers/infiniband/ulp/ipoib/ipoib_verbs.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)

If you care about IPoIB performance you should be using the
accelerated IPoIB stuff, the drivers implementing that all provide
much better handling of CQ affinity.

What scenario does this patch make a difference?

Jason