Runtime Checking of Datatype Signatures in MPI

Abstract. The MPI standard provides a way to send and receive complex combinations of datatypes (e.g., integers and doubles) with a single communication operation. The MPI standard speci es that the type signature, that is, the basic datatypes (language-de ned types such as int or DOUBLE PRECISION), must match in communication operations such as send/receive or broadcast. Because datatypes may be de ned by the user in MPI, there is a limitless collection of possible type signatures. Detecting the programmer error of mismatched datatypes is di cult in this case detecting all errors essentially requires sending a complete description of the type signature with a message. This paper discusses an alternative: send the value of a function of the type signature so that (a) identical type signatures always give the same function value, (b) different type signatures often give di erent values, and (c) common cases (e.g., prede ned datatypes) are handled exactly. Thus, erroneous programs are of...

• Type: Conference
• Year: 2000
• Where: PVM
• Authors: William Gropp
• Keywords: Communication Operations, Datatypes, Distributed And Parallel Computing, PVM 2000, Type Signatures