On Fri, Jan 18, 2008 at 11:43:03AM -0500, Jeff Squyres wrote:
> I think the main savings is that mellanox hardware works better when
> fewer qp's are open. I.e., it's a resource issue on the HCA, not
> necessarily a savings in posting buffers to the qp.
Interesting. I hear this justification
It easy to see the benefit of fewer qps (per node instead of per peer)
and less consumption of resources the better but I am curious about
the actual percentage of memory footprint decrease. I am thinking that
the largest portion of the footprint comes from the fragments.
BTW here is link to
I think the main savings is that mellanox hardware works better when
fewer qp's are open. I.e., it's a resource issue on the HCA, not
necessarily a savings in posting buffers to the qp.
But it's quite a complicated issue. :-)
Gleb has some reservations about XRC; I'll let him expound on
Those pointers were perfect thanks.
It easy to see the benefit of fewer qps (per node instead of per peer)
and less consumption of resources the better but I am curious about the
actual percentage of memory footprint decrease. I am thinking that the
largest portion of the footprint comes from
Here is paper from openib http://www.openib.org/archives/nov2007sc/XRC.pdf
and here is mvapich presentation
http://mvapich.cse.ohio-state.edu/publications/ofa_nov07-mvapich-xrc.pdf
Button line: XRC decrease number of QPs that ompi opens and as result
decrease ompi's memory footprint.
In the
Hi,
After searching, about the only thing I can find on xrc is what it
stands for, can someone explain the benefits of open mpi's use of xrc,
maybe point me to a paper, or both?
TIA
-DON
