Give less space to the communicators and groups episodes in favor of more in-depth treatment of datatypes.
To change
Clarify the meaning of displacements in the typemap
In the my_pair type-along, the addresses are relative to whatever MPI thinks is the first byte in memory. Make it so that they are relative to the first field in the data structure
Clarify why/when to use pack/unpack and why/when to define datatypes.
The former can incur overhead, e.g. calls to functions in a dynamically linked library (-lmpi) are slower than calls to functions in your executable.
The latter is essential if we want to perform reductions with a custom operation.
To add
Defining custom operations on custom datatypes. This could fit in the collective episode.
Short discussion of whether it is possible to automatically generate the MPI representation of custom datatypes.
Automatic serialization/deserialization libraries (like Cereal for C++) but using these is not exactly the same as defining datatypes, e.g. you can't do custom reductions.
Introspection. Possible in C++ with metaprogramming, but do you really want to go there? :smile:
Code generation. Build is in two passes then: first generate the code (the generation of the code needs some tool to analyze the AST) then compile it.
To consider
To change
my_pairtype-along, the addresses are relative to whatever MPI thinks is the first byte in memory. Make it so that they are relative to the first field in the data structure-lmpi) are slower than calls to functions in your executable.To add