BIB-VERSION:: CS-TR-v2.0
ID:: ncstrl.dartmouthcs//TR95-253
ENTRY:: March 10, 1995
ORGANIZATION:: Dartmouth College, Computer Science
TITLE:: Low-level Interfaces for High-level Parallel I/O
TYPE:: Technical Report (paper)
REVISION:: 1
AUTHOR:: Nieuwejaar, Nils
AUTHOR:: Kotz, David
DATE::		March 1995
RETRIEVAL:: For a paper copy, email <reports@cs.dartmouth.edu>
RETRIEVAL:: For a paper copy, write to
       Technical Report Librarian
       Department of Computer Science
       Dartmouth College
       6211 Sudikoff Laboratory
       Hanover, NH 03755-3510
       USA
RETRIEVAL:: Compressed Postscript at http://www.cs.dartmouth.edu/reports/TR95-253.ps.Z
RETRIEVAL:: PDF at http://www.cs.dartmouth.edu/reports/TR95-253.pdf
ABSTRACT::
As the I/O needs of parallel scientific applications increase, file
systems for multiprocessors are being designed to provide applications
with parallel access to multiple disks.  Many parallel file systems
present applications with a conventional Unix-like interface that
allows the application to access multiple disks transparently.  By
tracing all the activity of a parallel file system in a production,
scientific computing environment, we show that many applications
exhibit highly regular, but non-consecutive I/O access patterns.
Since the conventional interface does not provide an efficient method
of describing these patterns, we present three extensions to the
interface that support strided, nested-strided, and nested-batched I/O
requests.  We show how these extensions can be used to express common
access patterns.
NOTE::
This TR supercedes PCS-TR94-230.
NOTE::
A result of the <A HREF="/~dfk/charisma.html">CHARISMA project</A>.
NOTE::
Appeared in <A HREF="/iopads/iopads95/">IOPADS '95</A> at IPPS '95.
END:: ncstrl.dartmouthcs//TR95-253