Designing C++ memory pools to avoid dynamic memory allocations
We have had several discussions on dynamic memory allocation, the steps the OS needs to perform, and why dynamic memory allocation is slow. Dynamic memory allocation is so slow in fact that low latency applications actively try to avoid it as much as possible on the critical path. We cannot build useful applications without creating and deleting many objects at runtime, and dynamic memory allocation is too slow for low latency applications.
Understanding the definition of a memory pool
First, let us formally define what a memory pool is and why we need one. Many applications (including low latency applications) need to be able to handle many objects and an unknown number of objects. By an unknown number of objects, we mean that the expected count of objects cannot be determined ahead of time, and it cannot be ascertained what the maximum number of objects will be. Obviously, the maximum number of objects possible...
