# Improving Parallel Local Search for SAT

@inproceedings{Arbelaez2011ImprovingPL, title={Improving Parallel Local Search for SAT}, author={Alejandro Arbelaez and Youssef Hamadi}, booktitle={Learning and Intelligent Optimization}, year={2011} }

In this work, our objective is to study the impact of knowledge sharing on the performance of portfolio-based parallel local search algorithms. Our work is motivated by the demonstrated importance of clause-sharing in the performance of complete parallel SAT solvers. Unlike complete solvers, state-of-the-art local search algorithms for SAT are not able to generate redundant clauses during their execution. In our settings, each member of the portfolio shares its best configuration (i.e., one…

## 23 Citations

### Parallel Local Search for Satisfiability

- Computer Science
- 2013

This chapter studies the impact of knowledge sharing on the performance of portfolio-based parallel local search algorithms, which aggregates the shared knowledge to carefully craft a new starting point at each restart point.

### From Sequential to Parallel Local Search for SAT

- Computer ScienceEvoCOP
- 2013

An empirical study is presented that suggests that the best sequential solver is not necessary the one with the overall best parallel speedup, and that on different problem families the behaviors of different solvers vary greatly.

### Cooperative Parallel SAT Local Search with Path Relinking

- Computer ScienceEvoCOP
- 2020

An empirical study is presented that suggest that path relinking outperforms a set of well-known parallel portfolio-based local search algorithms with and without cooperation.

### Massively Parallel Local Search for SAT

- Computer Science2012 IEEE 24th International Conference on Tools with Artificial Intelligence
- 2012

This work studies the performance of parallel local search for SAT with a large degree of parallelism, up to 256 cores, and compares various cooperation strategies.

### Towards Massively Parallel Local Search for SAT - (Poster Presentation)

- Computer ScienceSAT
- 2012

Parallel portfolio-based algorithms have become a standard methodology for building parallel algorithms for SAT and strategies range from a voting mechanism where each algorithm in the portfolio suggests a value for each variable to probabilistic constructions.

### Parallel Tree Search for Satisfiability

- Computer Science
- 2013

ManySAT is described, a portfolio-based parallel SAT solver which runs a set of complementary sequential algorithms obtained through careful variations of the standard CDCL algorithm which shares clauses to improve the overall performance of the whole system.

### An overview of parallel SAT solving

- Computer ScienceConstraints
- 2012

This paper presents an overview of parallel SAT solving, namely, different approaches and a variety of clause sharing strategies, and an evaluation of multicore SAT solvers is presented, showing the evolution of multicores over the last years.

### A review of literature on parallel constraint solving

- Computer ScienceTheory and Practice of Logic Programming
- 2018

There seems to be little overall guidance that can be given on how best to exploit multi-core computers to speed up constraint solving, and it is hoped that this survey will provide useful pointers to future researchers wishing to correct this situation.

### Seven Challenges in Parallel SAT Solving

- Computer ScienceAI Mag.
- 2013

This paper provides a broad overview of the situation in the area of Parallel Search with a specific focus on Parallel SAT Solving. A set of challenges to researchers is presented which, we…

### Estimating parallel runtimes for randomized algorithms in constraint solving

- Computer ScienceJ. Heuristics
- 2016

A framework to estimate the parallel performance of a given algorithm by analyzing the runtime behavior of its sequential version by approximating the runtime distribution of the sequential process with statistical methods is proposed.

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