Parallella memory barriers and traffic white paper

Here is a white paper from bitware, an FPGA manufacturer who used epiphany chips, that explains the barrier structure for synchronized operation and also a little bit about inner chip core communication and traffic. Nice imformative short read.
http://www.bittware.com/wp-content/uplo ... arrier.pdf
http://www.bittware.com/wp-content/uplo ... arrier.pdf