GASNet

"GASNet is a language-independent, low-level networking layer that provides network-independent, high-performance communication primitives tailored for implementing parallel global address space SPMD languages and libraries such as UPC, UPC++, Co-Array Fortran, Legion, Chapel, and many others. The interface is primarily intended as a compilation target and for use by runtime library writers (as opposed to end users), and the primary goals are high performance, interface portability, and expressiveness. GASNet stands for "Global-Address Space Networking". 

 The design of GASNet is partitioned into two layers to maximize porting ease without sacrificing performance: the lower level is a narrow but very general interface called the GASNet core API - the design is based heavily on Active Messages, and is implemented directly on top of each individual network architecture. The upper level is a wider and more expressive interface called the GASNet extended API, which provides high-level operations such as remote memory access and various collective operations."

http://gasnet.lbl.gov/

https://github.com/mbdriscoll/pygas