parXXL is a library for large scale computation and communication that executes fine grained algorithms (computation and communication are of the same order of magnitude) on coarse grained architectures (clusters, grids, mainframes).
Historically parXXL the result of a merge of two different projects, ParCeL (from Supélec) and SSCRAP (from INRIA), that stand for a consequent modeling and implementation of fine grained networks (ParCeL ) and coarse grained algorithmics (SSCRAP ) respectively.
The integration, testing and benchmarking of parXXL started as a joint effort with Amelia De Vivo, university of Basilicata, Ponteza, Italy, until her sudden and unexpexted death in June 2006.
This library takes the requirements of PRO , see Section 3.1 , into account, i.e., the design of algorithms in alternating computation and communication steps. It realizes an abstraction layer between the algorithm as it was designed and its realization on different architectures and different modes of communication. The current version of this library is available at http://parxxl.gforge.inria.fr/ and integrates:
a layer for message passing with MPI ,
a layer for shared memory with POSIX threads , and,
a layer for out-of-core management with file mapping (system call mmap ).
All three different realizations of the communication layers are quite efficient. They let us execute programs that are otherwise unchanged within the three different contexts such that they reach or maybe outperform programs that are directly written for them.