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Reviewer: Lorie M. Liebrock

MPI is an attempt to bring together the best features of many existing message-passing systems, while showing that parallel processing need not compromise efficiency, portability, and functionality. In addition to providing standard message-passing capabilities, MPI extends the notion of a message tag to define a context that is allocated at runtime. Contexts allow user programs and libraries to maintain separate “message spaces.” A communicator is defined by the context and the group of processes. Communicators define precisely which processes are involved in a communication. Just as the pattern of communication, or application topology, is an integral part of an application, the definition of the virtual topology is an integral part of MPI. Cartesian topologies are predefined with special operations such as shift. Other MPI features include support for debugging, profiling, blocking and nonblocking communication, libraries, and heterogeneous networks of processors. In the first part of the book, beginning with a small but sufficient set of routines, MPI is introduced in terms of what is needed to solve particular problems. This approach is used through the first six chapters. More advanced features are introduced with the focus on the feature instead of the application, but still with coding examples. The authors alternate between the use of Fortran and C in the examples used to introduce MPI functionality. Only occasionally is this mixing of languages confusing or distracting. The MPI routine summary has two parts—one for C and one for Fortran. This book provides an easy introduction to parallel programming with MPI. Throughout the work, MPI implementors' choices are often pointed out to warn users of the possibility of variation in implementations. The chapter on implementation specifically discusses how MPI interacts with an abstract device interface. The porting sections show how to translate from another (source) language; for example, Intel NX to MPI (target), starting with basics such as initialization, sending, receiving, and termination. Collective operations, other features with counterparts, and features of the source language that are not included in the MPI are also discussed. Each porting section ends with comments on process startup. Overall, this material is easy to follow, but there are a few problems. Occasionally, incorrect function names are used. Also, a few of the examples use programming logic that is confusing. In one, there is a computed goto (with 8 branches), and 9 of 16 lines of code are labeled. In this example, only 2 of the unlabeled lines are not gotos. This confusing style, however, is the exception, rather than the rule, for the coding examples in the book. Other minor difficulties include not being able to distinguish patterns in the upshot figures, using C notation (!converged) in flowcharts, and giving an invalid address for the “frequently asked questions” page on the World Wide Web (a currently working address is http://www.erc.msstate.edu/mpi/mpi-faq.html).