MEL is a C++11, header-only library, being developed with the goal of creating a light weight and robust framework for building parallel applications on top of MPI. MEL is designed to introduce no (or minimal) overheads while drastically reducing code complexity. It allows for a greater range of common MPI errors to be caught at compile-time rather than during program execution where it can be far more difficult to debug what is going wrong.
A good example of this is type safety in the MPI standard. The standard does not dictate how many of the object types should be implemented leaving these details to
the implementation vendor. For instance, in Intel MPI 5.1 MPI_Comm objects and many other simple types are implemented as indexes, typedef int MPI_Comm
, leaving the implementation to use these indexes to manage the real objects internally. A drawback with this approach is it causes compile time type-checking of
function parameters to not flag erroneous combinations of variables. The common signature MPI_Send(void*, int, MPI_Datatype, int, int, MPI_Comm) is actually seen
by the compiler as MPI_Send(void*, int, int, int, int, int), allowing any ordering of the last five variables to be compiled as valid MPI code, while causing
catastrophic failure at run-time. In contrast, OpenMPI 1.10.2 implements these types as structs which are inherently type-safe.
With MEL we aim to provide a consistent and unified function syntax that allows all MPI distributions to behave in a common and predictable way; while also providing some higher-level functionality that is not available from the MPI standard such as deep-copy, mutexes, RMA shared memory synchronization, and more.
We plan to keep MEL in active development and hope that the research community will join us as we continue to grow the features and capabilities encompassed within the project. MEL is Open-Source and available on Github under the MIT license at: https://github.com/CS-Swansea/MEL .
std::array/std::vector by start/end iterators.