Minimizing the usage of hardware counters for collective communication using triggered operations
Nusrat Sharmin Islam, Gengbin Zheng, Sayantan Sur, Akhil Langer, María Jesús Garzarán · 2019
Triggered operations and counting events or counters are building blocks that can be used by communication libraries, such as MPI, to offload collective operations to the Host Fabric Interface (HFI) or Network Interface Card (NIC). Triggered operations can be used to schedule a network or arithmetic operation to occur in the future, when a trigger counter reaches a specified threshold. On completion of the operation, the value of a completion counter increases by one. With this mechanism, it is possible to create a chain of dependent operations, so that the execution of an operation is triggered when all its dependent operations have completed its execution.