LogSC: Model-based one-sided communication performance estimation

Abstract

One-sided communication (also known as remote memory access, or RMA) in the Message Passing Interface (MPI) is a communication interface that has been introduced in MPI-2 (1997) that enables new more efficient programming models. In MPI-3, some new more flexible and efficient primitives have been introduced, which makes it easier to use and more deployable.However, compared to traditional two-sided communication, little work has been performed on analyzing one-sided communication costs, which urgently requires formal analysis. The communication performance model is a formal analysis of communication and its cost. We focus on the software model, whose core idea is that the transmission can be represented as a sequence of implicit transfers and data movements. This approach is a suitable solution for concurrent communication modeling.We propose LogSC, which consists of the window cost, transmission cost, synchronization cost, and computational cost in atomic operations. In this paper, LogSC is used to model most of the operations in one-sided communication, including the put/get operation, atomic operation, and shared memory programming of MPI. We model and evaluate the parallel tests of IMB, collectives designed by combining MPI and the MPI shared memory (MPI+MPI), and the communication in the scalable universal matrix multiplication algorithm (SUMMA), which is a common matrix multiplication algorithm. Experiments show that our modeling has high accuracy, which makes up for the lack of existing models.