Performance considerations in software multicasts
J. Cordsen, H. W. Pohl, Wolfgang Schröder‐Preikschat · 1997
Parallel computation environments exploiting conventional processors offer the potential to achieve high efficiency at a low cost.In the future, even heterogeneous clusters of symmetric multiprocessors (SMPs) will supersede special purpose computers.Due to this trend, the availability of special hardware support for global communication will be more unusual For such an environment, software-implemented multicasts and broadcasts are highly demanded to support a global dissemination of information over networks of processors.This article introduces the theory and presents an algorithm for the implementation of an one-source/manydestination distribution of a message (multicast communication) based on a send-and-forget semantic, i.e. the event of sending a message performs asynchronously with respect to the blocking receive event.The performance of a multicast communication is sensitive to the underlying communication system.In order to achieve optimal results, the algorithm must consider the latencies at the sending and receiving sites.It is shown that computing systems with a low probability for contentions in the communication network offer optimal performance results when they consider generalized Fibonacci sequences.Experiments on a parallel computing system and comparisons with related work demonstrate the relevance of the proposed work. introductionThe efficiency of communication is important to the overall system performance.Especially, this is true in large-scale computing systems consisting of distributed memory computing resources.Many message-passing communication libraries (e.g.PVM or MPI) are available and allow for a portable programming of parallel applications.Message-passing communication services can be grouped into two classes: point-to-point and collective operations.Point-to-point communications involves two communication partners in the form of various modes of send and receive operations, e.g.blocking or non-blocking semantics.A col-Penniwion to make digitniihnrd copies ofall or pnri ofthis mnterial for personrl or chwsroom use is granted without fee provided thnt the copies 'we not made or distributed for protit or commercial rdvantrtge, the copyright notice, the title ofthe puhlic~tion nnd it.<&te nppenr, nnd notice ix given tbnt