Home

Global Arrays (GA) is a Partitioned Global Address Space (PGAS) programming model. It provides primitives for one-sided communication (Get, Put, Accumulate) and Atomic Operations (read increment). It supports blocking and non-blocking primtives, and supports location consistency.

Starting with GA v5.4, ARMCI has been deprecated and replaced with Communication runtime for Extreme Scale (ComEx). GA uses ComEx to abstract inter-node communication operations. The default ComEx ports use MPI --- which makes GA and ComEx portable for high-end systems. Most ComEx implementations use on-node shared memory for faster intra-node communication.