Efficient algorithms for all-to-all communications in multiport mesage passing system

Efficient algorithms for all-to-all communications in multiport mesage passing system

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS, VOL. 8, NO. 11, NOVEMBER 1997 1143 Efficient Algorithms for All-to-All Communications in Multiport Message-Passing Systems Jehoshua Bruck, Senior Member , IEEE , Ching-Tien Ho, Member , Shlomo Kipnis, , Eli Upfal, , and Derrick Weathersby Abstract —We present efficient algorithms for two all-to-all communication operations in message-passing systems: index (or all-to- all personalized communication) and concatenation (or all-to-all broadcast). We assume a model of a fully connected message- passing system, in which the performance of any point-to-point communication is independent of the sender-receiver pair. We also assume that each processor has k 1 ports, through which it can send and receive messages in every communication round. The complexity measures we use are independent of the particular system topology and are based on the communication start-up time, and on the communication bandwidth. In the index operation among n processors, initially, each processor has blocks of data, and the goal is to exchange the i th block of processor j with the th block of processor . We present a class of index algorithms that is designed for all values of and that features a trade-off between the communication start-up time and the data transfer time. This class of algorithms includes two special cases: an algorithm that is optimal with respect to the measure of the start-up time, and an algorithm that is optimal with respect to the measure of the data transfer time. We also present experimental results featuring the performance tuneability of our index algorithms on the IBM SP-1 parallel system. In the concatenation operation, among processors, initially, each processor has one block of data, and the goal is to concatenate the blocks of data from the processors, and to make the concatenation result known to all the processors. We present a concatenation algorithm that is optimal, for most values of , in the number of communication rounds and in the amount of data transferred. Index Terms —All-to-all broadcast, all-to-all personalized communication, complete exchange, concatenation operation, distributed- memory system, index operation, message-passing system, multiscatter/gather, parallel system. —————————— —————————— 1I NTRODUCTION ollective communication operations [2] are communica- tion operations that generally involve more than two processors, as opposed to the point-to-point communication between two processors. Examples of collective communica- tion operations include: (one-to-all) broadcast, scatter, gather, index (all-to-all personalized communication), and concate- nation (all-to-all broadcast). See [13], [16] for a survey of col- lective communication algorithms on various networks with various communication models.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 14

Efficient algorithms for all-to-all communications in multiport mesage passing system

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online