Empirical study of parallel SQL query execution

Abstract

In this paper we experiment with two major types of query parallelization techniques - intra and inter operator parallelism and their combinations. We evaluate these techniques applied to a query tree with a number of join operators in the multithreaded environment. In our experiments we vary thread count, buffer size, workload characteristics, measure the relative performance of several distinct join algorithms and observe several modes which appear in the series of experiments.

Keywords

• базы данных, эксперименты, параллелизм, многопоточность, исполнение запросов