A study of dynamic memory management in C++ programs

Recently, the importance of dynamic memory management has been increased significantly as there is a growing number of development in object-oriented programs. Many studies show that dynamic memory management is one of the most expensive components in many software systems. It can consume up to 30% of the program execution time. Especially, in C++ programs, it tends to have object creation and deletion prolifically. These objects tend to have short life-spans. This paper describes an integrated study of the C++'s memory allocation behavior, a memory tracing tool and memory managements based on the empirical study of C++ programs. First, this paper summarizes the hypothesis of situations that invoke the dynamic memory management explicitly and implicitly. They are: constructors, copy constructors, overloading assignment operator=, type conversions and application specific member functions. Second, a dynamic memory tracing tool, called mtrace++, is introduced to study the dynamic memory allocation behavior in C++ programs. Third, a dynamic memory allocation strategy, called O-Reuse, to reuse the allocated objects to speed up the object management. At the later part of this paper, an automatic dynamic memory management, called GC++, is discussed. GC++ collects unreferenced objects automatically with high speed of allocation/deallocation processes. The performance gains of O-Reuse and GC++ are come from the utilization of memory allocation/deallocation behavior.