Paper Info
Title
Evaluation of an Eager Protocol Optimization for MPI
Abstract
Nearly all implementations of the Message Passing Interface (MPI) employ a two-level protocol for point-to-point messages. Short messages are sent eagerly to optimize for latency, and long messages are typically implemented using a rendezvous mechanism. In a rendezvous implementation, the sender must first send a request and receive an acknowledgment before the data can be transferred. While there are several possible reasons for using this strategy for long messages, most implementations are forced to use a rendezvous strategy due to operating system and/or network limitations. In this paper, we compare an implementation that uses a rendezvous protocol for long messages with an implementation that adds an eager optimization for long messages. We discuss implementation issues and provide a performance comparison for several microbenchmarks. We also present a new micro-benchmark that may provide better insight into how these different protocols effect application performance. Results for this new benchmark indicate that, for larger messages, a significant number of receives must be pre-posted in order for an eager protocol optimization to outperform a rendezvous protocol.
Year
DOI
Venue
2003
10.1007/978-3-540-39924-7_46
Lecture Notes in Computer Science
Keywords
Field
DocType
point to point,message passing interface,operating system
Latency (engineering),Computer science,Communication source,Implementation,Message Passing Interface,Rendezvous,Transmission protocol,Message passing,Message size,Distributed computing
Conference
Volume
ISSN
Citations 
2840
0302-9743
20
PageRank 
References 
Authors
1.34
4
2
Name
Order
Citations
PageRank
Ron Brightwell1106094.72
Keith D. Underwood284777.39