Title
Distributed SBP Cholesky factorization algorithms with near-optimal scheduling
Abstract
The minimal block storage Distributed Square Block Packed (DSBP) format for distributed memory computing on symmetric and triangular matrices is presented. Three algorithm variants (Basic, Static, and Dynamic) of the blocked right-looking Cholesky factorization are designed for the DSBP format, implemented, and evaluated. On our target machine, all variants outperform standard full-storage implementations while saving almost half the storage. Communication overhead is shown to be virtually eliminated by the Static and Dynamic variants, both of which take advantage of hardware parallelism to hide communication costs. The Basic variant is shown to yield comparable or slightly better performance than the full-storage ScaLAPACK routine PDPOTRF while clearly outperformed by both Static and Dynamic. Models of execution assuming zero communication costs and overhead are developed. For medium- and larger-sized problems, the Static schedule is near optimal on our target machine based on comparisons with these models and measurements of synchronization overhead.
Year
DOI
Venue
2009
10.1145/1499096.1499100
ACM Trans. Math. Softw.
Keywords
Field
DocType
distributed square block format,sbp cholesky factorization algorithm,synchronization overhead,packed storage,parallel computing,communication overhead,minimal block storage,positive definite matrices,full-storage scalapack routine pdpotrf,communication cost,dynamic variant,real symmetric matrices,zero communication cost,static schedule,dsbp format,near-optimal scheduling,parallel algorithms,target machine,cholesky factorization,distributed memory,parallel computer,symmetric matrices,parallel algorithm
Scheduling (computing),Matrix (mathematics),Computer science,Theoretical computer science,Cholesky decomposition,Synchronization,Mathematical optimization,Parallel algorithm,Parallel computing,Distributed memory,Algorithm,Block (data storage),ScaLAPACK
Journal
Volume
Issue
ISSN
36
2
0098-3500
Citations 
PageRank 
References 
9
0.84
14
Authors
3
Name
Order
Citations
PageRank
Fred G. Gustavson11185223.40
Lars Karlsson2515.16
Bo Kågström31045189.17