ENSEMBLE: A communication layer for embedded multi-processor systems

The ENSEMBLE communication library exploits overlapping of message aggregat ion (computation) and DMA transfers (communication) for embedded multi-proc essor systems. In contrast to traditional communication libraries, ENSEMBLE operates on n-dimensional data descriptors that can be used to specify oft en-occurring data access patterns in n-dimensional arrays. This allows ENSE MBLE to setup a three-stage pack-transfer-unpack pipeline, effectively over lapping message aggregation and DMA transfers. ENSEMBLE is used to support Spar/Java, a Java-based language with SPMD annotations. Measurements on a T riMedia-based multi-processor system show that ENSEMBLE increases performan ce up to 39% for peer-to-peer communication, and up to 34% for all-to-all c ommunication.