How Do You Implement a Custom Allocator in C++?

How Do You Implement a Custom Allocator in C++?

Custom allocators provide greater control over memory management in C++. They can optimize memory usage.

To implement one, you need to define allocation and deallocation functions. Here’s an example:

            template
            struct MyAllocator {
                T* allocate(std::size_t n) { return static_cast(::operator new(n * sizeof(T))); }
                void deallocate(T* p, std::size_t) { ::operator delete(p); }
            };
            

Custom allocators can reduce fragmentation and improve cache performance. They are essential in systems where performance is critical.

Implementing an allocator allows you to fine-tune memory management to fit specific application needs.