arrow
Return

Efficient Task Graph Scheduling for Parallel QR Factorization in SLSQP

delete2026-01-01
delete0
PRE
AI
S
Soumyajit Chatterjee *
R
Rahul Utkoor
U
Uppu Eshwar
S
Sathya Peri
V
V. Krishna Nandivada
DOI:10.1007/978-3-031-99872-0_15delete
deleteOriginal
deleteOriginal request for help
deleteShare
deleteSave
Abstract

Abstract

En 中文
Efficient task scheduling is paramount in parallel programming on multi-core architectures, where tasks are fundamental computational units. QR factorization is a critical sub-routine in Sequential Least Squares Quadratic Programming (SLSQP) for solving non-linear programming (NLP) problems. QR factorization decomposes a matrix into an orthogonal matrix Q and an upper triangular matrix R, which are essential for solving systems of linear equations arising from optimization problems. SLSQP uses an in-place version of QR factorization, which requires storing intermediate results for the next steps of the algorithm. Although DAG-based approaches for QR factorization are prevalent in the literature, they often lack control over the intermediate kernel results, providing only the final output matrices Q and R. This limitation is particularly challenging in SLSQP, where intermediate results of QR factorization are crucial for back-substitution logic at each iteration. Our work introduces novel scheduling techniques using a two-queue approach to execute the QR factorization kernel effectively. This approach, implemented in high-level C++ programming language, facilitates compiler optimizations and allows storing intermediate results required by back-substitution logic. Empirical evaluations demonstrate substantial performance gains, including a 10x improvement over the sequential QR version of the SLSQP algorithm.
Keywords:
Non Linear Programming
Parallel Computing
DAG Sch-eduling

Journal

E
EURO-PAR 2025: PARALLEL PROCESSING, PT III
IF:
0
Papers:
21
Citations:
0

Organization

Q
qualcomm
Scholars:
781
Papers: 645
Citations: 1
I
indian institute of technology system (iit system)
Scholars:
9.5W
Papers: 9.9W
Citations: 93
I
indian institute of technology (iit) - hyderabad
Scholars:
1.8K
Papers: 1.7K
Citations: 7
researcher View more organizations