Escali 4.4 manual Description of Scali MPI Connect, Scali MPI Connect components

Chapter 2 Description of Scali MPI Connect

This chapter gives the details of the operations of Scali MPI Connect (SMC). SMC consists of libraries to be linked and loaded with user application program(s), and a set of executables which control the start-up and execution of the user application program(s). The relationship between these components and their interfaces are described in this chapter. It is necessary to understand this chapter in order to control the execution of parallel processes and be able to tune Scali MPI Connect for optimal application performance.

2.1 Scali MPI Connect components

Scali MPI Connect consists of a number of programs, daemons, libraries, include and configuration files that together implements the MPI functionality needed by applications. Starting applications rely on the following daemons and launchers:

•mpimon is a monitor program which is the user’s interface for running the application program.

•mpisubmon is a submonitor program which controls the execution of application programs. One submonitor program is started on each node per run.

•mpiboot is a bootstrap program used when running in manual-/debug-mode.

•mpid is a daemon program running on all nodes that are able to run SMC. mpid is used for starting the mpisubmon programs (to avoid using Unix facilities like the remote shell rsh). mpid is started automatically when a node boots, and must run at all times

Figure 2-1:The way from application startup to execution

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