Techniques to provide run-time support for solving irregular problems

Jaechun No*, Alok Choudhary

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations


In this paper we present a runtime library design based on the two-phase collective I/O technique for irregular applications. The design is motivated by the requirements of a large number of ASCI (Accelerated Strategic Computing Initiative) applications, although the design and interface is general enough to be used from any irregular applications. We present two designs, namely, `Collective I/O' and `Pipelined Collective I/O'. In the first scheme, all processors participate in the I/O at the same time, making scheduling of I/O requests simpler but creating a possibility of contention at the I/O nodes. In the second approach, processors are grouped into several groups, so that only one group performs I/O simultaneously, while the next group performs communication to rearrange data, and this entire process is pipelined. This reduces the contention at the I/O nodes but requires more complicated .scheduling and a possible degradation in communication performance. We obtained up to 40 MBytes/sec. application level performance on the Caltech's Intel Paragon (with 16 IO nodes, each containing one disk) which includes on-the-fly reordering costs. We observed up to 60 MBytes/sec on the ASCI/Red machine with only three I/O nodes (with RAIDS).

Original languageEnglish (US)
Title of host publicationProceedings of the Internatoinal Conference on Parallel and Distributed Systems - ICPADS
Editors Anon
PublisherIEEE Comp Soc
Number of pages8
StatePublished - Dec 1 1997
EventProceedings of the 1997 International Conference on Parallel and Distributed Systems - Seoul, South Korea
Duration: Dec 10 1997Dec 13 1997


OtherProceedings of the 1997 International Conference on Parallel and Distributed Systems
CitySeoul, South Korea

ASJC Scopus subject areas

  • Hardware and Architecture


Dive into the research topics of 'Techniques to provide run-time support for solving irregular problems'. Together they form a unique fingerprint.

Cite this