What if MPI Collective Operations Were Instantaneous?
نویسندگان
چکیده
Collective MPI operations are an interesting research topic, since their implementation is complex and there are many different possible ways to improve their performance. It is not always obvious how much a given application will gain from such improvements and some of the methods to improve collective performance are costly and time-consuming to implement. In this paper we use a hybrid MPI simulator to run benchmarks and applications with the cost of collective operations set to zero. This allows us to gather performance data that shows how much at most an application could benefit from better collective operations.
منابع مشابه
Verifying Collective MPI Calls
The collective communication operations of MPI, and in general MPI operations with non-local semantics, require the processes participating in the calls to provide consistent parameters, eg. a unique root process, matching type signatures and amounts for data to be exchanged, or same operator. Exhaustive consistency checks are typically too expensive to perform under normal use of MPI and would...
متن کاملPipelining and Overlapping for MPI Collective Operations
Collective operations are an important aspect of the currently most important message-passing programming model MPI (Message Passing Interface). Many MPI applications make heavy use of collective operations. Collective operations involve the active participation of a known group of processes and are usually implemented on top of MPI point-to-point message passing. Many optimizations of the used...
متن کاملMPI Collective Operations over IP Multicast
Many common implementations of Message Passing Interface (MPI) implement collective operations over point-to-point operations. This work examines IP multicast as a framework for collective operations. IP multicast is not reliable. If a receiver is not ready when a message is sent via IP multicast, the message is lost. Two techniques for ensuring that a message is not lost due to a slow receivin...
متن کاملD RA FT 10 / 1 4 / 20 08 Non - Blocking Collective Operations for MPI - 3 The MPI - 3 Collective Operations
We propose new non-blocking interfaces for the collective group communication functions defined in MPI1 and MPI-2. This document is meant as a standard extension and written in the same way as the MPI standards. It covers the MPI-API as well as the semantics of the new operations.
متن کاملImplementing MPI-2 Extended Collective Operations1
This paper describes a first approach to implement MPI-2’s Extended Collective Operations. We aimed to ascertain the feasibility and effectiveness of such a project based on existing algorithms. The focus is on the intercommunicator operations, as these represent the main extension of the MPI-2 standard on the MPI-1 collective operations. We expose the algorithms, key features and some performa...
متن کامل