Using transitive closure and transitive reduction to extract coarse-grained parallelism in program loops
نویسندگان
چکیده
A technique for extracting coarse-grained parallelism available in loops is presented. It is based on splitting a set of dependence relations into two sets. The first one is to be used for generating code scanning slices while the second one permits us to insert send and receive functions to synchronize the slices execution. The paper presents a way demonstrating how to remove redundant synchronization in generated code by means of the transitive reduction operation. Results of experiments – how many synchronization points can be removed, speed-up and efficiency of examined parallel loops are discussed.
منابع مشابه
Transitive Closure of a Union of Dependence Relations for Parameterized Perfectly-Nested Loops
This paper presents a new approach for computing the transitive closure of a union of relations describing all the dependences in both uniform and quasi-uniform perfectly-nested parameterized loops. This approach is based on calculating the basis of a dependence distance vectors set. The procedure has polynomial time complexity for most steps of calculations. This allows us to effectively extra...
متن کاملThe Effect of Transitive Closure on the Calibration of Logistic Regression for Entity Resolution
This paper describes a series of experiments in using logistic regression machine learning as a method for entity resolution. From these experiments the authors concluded that when a supervised ML algorithm is trained to classify a pair of entity references as linked or not linked pair, the evaluation of the model’s performance should take into account the transitive closure of its pairwise lin...
متن کاملCoarse-Grained Parallel Transitive Closure Algorithm: Path Decomposition Technique
We investigate the relation between fine-grained and coarse-grained distributed computations of a class of problems related to the generic transitive closure problem (TC for short). We choose an intricate systolic algorithm for the TC problem, by Guibas, Kung and Thompson (GKT algorithm for short), as a starting point due to its particularly close relationship to matrix multiplication. The GKT ...
متن کاملOn the PVM Computations of Transitive Closure and Algebraic Path Problems
We investigate experimentally, alternative approaches to the distributed parallel computation of a class of problems related to the generic transitive closure problem and the algebraic path problem. Our main result is the comparison of two parallel algorithms for transitive closure, { a straightforward coarse-grained parallel implementation of the Warshall algorithm named Block-Processing (whic...
متن کاملTwo-geodesic transitive graphs of prime power order
In a non-complete graph $Gamma$, a vertex triple $(u,v,w)$ with $v$ adjacent to both $u$ and $w$ is called a $2$-geodesic if $uneq w$ and $u,w$ are not adjacent. The graph $Gamma$ is said to be $2$-geodesic transitive if its automorphism group is transitive on arcs, and also on 2-geodesics. We first produce a reduction theorem for the family of $2$-geodesic transitive graphs of prime power or...
متن کامل