Parameters affecting the functionality of memory allocators

Parameters affecting the functionality of an operating system's memory management unit depend on a number of factors such as allocation and deallocation strategies, localization, internal and external fragmentation, regional clustering, allocation and deallocation speeds, multi-threading, reusability, wasted memory reusability, implementation level and dynamicity. In this paper, we examine different memory allocation methods used in the BSD operating system as well as parameters affecting the functionality of its memory management unit extracted from these methods. Besides identifying the relationships and dependencies between these parameters, we report our experimental measurements of the effect of each parameter on the performance of different memory management methods used in BSD. Our evaluations not only provide a comparative view of different allocation methods in BSD that have been deployed over time to complement each other, they also put into perspective different memory allocation methods used in different operating systems with respect to parameters such as multithreading ability, number of requests served and memory fragmentation rate.