BIB-VERSION:: CS-TR-v2.0
ID:: ncstrl.dartmouthcs//TR99-351
ENTRY:: June 10, 1999
ORGANIZATION:: Dartmouth College, Computer Science
TITLE:: Fast Out-of-Core Sorting on Parallel Disk Systems
TYPE:: Technical Report (paper)
REVISION:: 1
AUTHOR:: Pearson, Matthew D.
DATE:: June 1999
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/TR99-351.ps.Z
RETRIEVAL:: PDF at http://www.cs.dartmouth.edu/reports/TR99-351.pdf
ABSTRACT:: 
This paper discusses our implementation of Rajasekaran's
(l,m)-mergesort algorithm (LMM) for sorting on parallel disks. LMM is
asymptotically optimal for large problems and has the additional
advantage of a low constant in its I/O complexity. Our implementation
is written in C using the ViC* I/O API for parallel disk systems. 
	We compare the performance of LMM to that of the C library
function qsort on a DEC Alpha server. qsort makes a good benchmark
because it is fast and performs comparatively well under demand
paging. Since qsort fails when the swap disk fills up, we can only
compare these algorithms on a limited range of inputs. Still, on most
out-of-core problems, our implementation of LMM runs between 1.5 and
1.9 times faster than qsort, with the gap widening with increasing
problem size. 
NOTE:: 
Undergraduate Honors Thesis.  Advisor: Tom Cormen. 
END:: ncstrl.dartmouthcs//TR99-351