Performance Implications of Thread Count on OS Level Factors in Multithreaded Applications

Abstract

In high-performance computing, picking the right number of threads to gain a good speedup is important, as many OS-level parameters are influenced by even slight adjustments in thread count. These parameters are required by the operating system for process management and should not be ignored. They also contribute overhead to the running program, which can mount up quickly if not properly managed. Using too many threads in the system raises overheads, but using too few threads in the system significantly reduces performance. In this paper, the impact of page faults, CPU migrations, CPU utilisation, and context switching on execution time is investigated. The proposed work is simulated on a dual-socket Intel Xeon E5-2603 v3 using the well-known benchmark PARSEC 3.0. After studying performance parameters, simulation results reveal that running multithreaded programs with a correct number of threads can result in greater speedup and save overall system time.