Hi Eugene, Eugene Loh wrote: >> replace the fifo’s with a single link list per process in shared >> memory, with senders to this process adding match envelopes >> atomically, with each process reading its own link list (multiple
> *) Doesn't strike me as a "simple" change. Actually, it's much simpler than trying to optimize/scale the N^2 implementation, IMHO. > *) Not sure this addresses all-to-all well. E.g., let's say you post a > receive for a particular source. Do you then wade through a long FIFO > to look for your match? The tradeoff is between demultiplexing by the sender, which cost in time and in space, or by the receiver, which cost an atomic inc. ANY_TAG forces you to demultiplex on the receive side anyway. Regarding all-to-all, it won't be more expensive if the receives are pre-posted, and they should be. > What the RFC talks about is not the last SM development we'll ever > need. It's only supposed to be one step forward from where we are > today. The "single queue per receiver" approach has many advantages, > but I think it's a different topic. But is this intermediate step worth it or should we (well, you :-) ) go directly for the single queue model ? Patrick
