Scheduling data-flow graphs via retiming and unfolding

Author

Chao, Liang-Fang ; Sha, Edwin Hsing-Mean

Author_Institution

Dept. of Electr. Eng. & Comput. Eng., Iowa State Univ., Ames, IA, USA

Volume

8

Issue

12

fYear

1997

fDate

12/1/1997 12:00:00 AM

Firstpage

1259

Lastpage

1267

Abstract

Loop scheduling is an important problem in parallel processing. The retiming technique reorganizes an iteration; the unfolding technique schedules several iterations together. We combine these two techniques to obtain a static schedule with a reduced average computation time per iteration. We first prove that the order of retiming and unfolding is immaterial for scheduling a data-flow graph (DFG). From this nice property, we present a polynomial-time algorithm on the original DFG, before unfolding, to find the minimum-rate static schedule for a given unfolding factor. For the case of a unit-time DFG, efficient checking and retiming algorithms are presented

Keywords

computational complexity; data flow graphs; parallel programming; processor scheduling; checking; data-flow graphs; loop scheduling; polynomial-time algorithm; reduced average computation time; retiming; static schedule; unfolding; Chaos; Delay; Digital signal processing; High level synthesis; Iterative algorithms; Parallel processing; Polynomials; Processor scheduling; Scheduling algorithm; Very large scale integration;

fLanguage

English

Journal_Title

Parallel and Distributed Systems, IEEE Transactions on

Publisher

ieee

ISSN

1045-9219

Type

jour

DOI

10.1109/71.640018

Filename

640018