Experimental evaluation of performance and scalability of a multiprogrammed shared-memory multiprocessor

Chitra Natarajan, Ravishankar K. Iyer, Sanjay Sharma

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

Abstract

This paper investigates the performance and scalability of a shared-memory multiprocessor - the CEDAR supercomputer - in multiprogrammed environments. For the 4-cluster Cedar system, the overhead due to multiprogramming is 115% for the fine-grain loop parallel applications considered. There is no appreciable variation in the overhead as the multiprogramming level is increased. We find that while a single application executing on a dedicated system achieves significant speedups as the system is scaled up, in multiprogrammed environments however, there is no performance improvement with scaling. The interplay of two factors - unequal distribution of parallel work among the tasks and increased waiting times at the barriers - is found to be the major cause of the performance loss and poor scalability in multiuser environments. We find that the barrier wait time increases sharply as we go from a dedicated environment to one where 2 applications are multiprogrammed. However, the barrier wait time decreases as the multiprogramming level is increased further, due to the increasing inequality in the parallel work distribution.

Original languageEnglish (US)
Title of host publicationProceedings of the 5th IEEE Symposium on Parallel and Distributed Processing
Editors Anon
PublisherPubl by IEEE
Pages11-18
Number of pages8
ISBN (Print)081864222X
StatePublished - Dec 1 1993
Externally publishedYes
EventProceedings of the 5th IEEE Symposium on Parallel and Distributed Processing - Dallas, TX, USA
Duration: Dec 1 1993Dec 4 1993

Publication series

NameProceedings of the 5th IEEE Symposium on Parallel and Distributed Processing

Other

OtherProceedings of the 5th IEEE Symposium on Parallel and Distributed Processing
CityDallas, TX, USA
Period12/1/9312/4/93

ASJC Scopus subject areas

  • Engineering(all)

Fingerprint Dive into the research topics of 'Experimental evaluation of performance and scalability of a multiprogrammed shared-memory multiprocessor'. Together they form a unique fingerprint.

Cite this