ePubs
The open archive for STFC research publications
Home
About ePubs
Content Policies
News
Help
Privacy/Cookies
Suggest an Enhancement
Contact ePubs
Full Record Details
Persistent URL
http://purl.org/net/epubs/work/40804
Record Status
Checked
Record Id
40804
Title
On the Use of Parallel Input/Output in the High Performance Application Code, POLCOMS
Contributors
JV Ashby (CCLRC Rutherford Appleton Lab.)
,
M Ashworth (CCLRC Daresbury Lab.)
Abstract
As the problems addressed by High Performance Computational Science programs increase in size and complexity, the need for efficient input and output of datasets becomes an important factor in program design. Such datasets arise naturally as initial data and final results, but frequently programs save intermediate data during a long run to enable restarting the calculation in the event of a program or machine failure. Gathering all the data on one processor forms an inherent bottleneck, and for suitably large problems may exhaust the memory available to the master processor. We discuss the general problem of parallel I/O and the features of some of the available solutions. The checkpointing phase of a large High Performance scientific program, POLCOMS, is implemented in parallel using MPI-IO, a set of routines from the MPI-2 standard. The performance of MPI-IO is compared with that for gathering the data to one processor and writing it serially using a simple Fortran WRITE statement. We find that it is important to make sure the data representation being written out and the characteristics of access to the data are carefully selected, or serious performance degradation can be produced, as well as loss of flexibility. At its best, however, MPIIO is comparable with the naive process, and is capable of handling much larger problems.
Organisation
CCLRC
,
CSE
,
CSE-HEC
Keywords
CCP
,
parallel I/O
,
parallel input/output
Funding Information
Related Research Object(s):
Licence Information:
Language
English (EN)
Type
Details
URI(s)
Local file(s)
Year
Report
RAL Technical Reports
RAL-TR-2006-029. 2006.
polcoms-io.pdf
2006
Showing record 1 of 1
Recent Additions
Browse Organisations
Browse Journals/Series
Login to add & manage publications and access information for OA publishing
Username:
Password:
Useful Links
Chadwick & RAL Libraries
SHERPA FACT
SHERPA RoMEO
SHERPA JULIET
Journal Checker Tool
Google Scholar