Does STL Vector use 'new' and 'delete' for memory allocation by default?

Question

I am working on a plugin for an application, where the memory should be allocated by the Application and keep track of it. Hence, memory handles should be obtained from the host

Answer 1

vector uses std::allocator by default, and std::allocator is required to use global operator new (that is, ::operator new(size_t)) to obtain the memory (20.4.1.1). However, it isn't required to call it exactly once per call to allocator::allocate.

So yes, if you replace global operator new then vector will use it, although not necessarily in a way that really allows your implementation to manage memory "efficiently". Any special tricks you want to use could, in principle, be made completely irrelevant by std::allocator grabbing memory in 10MB chunks and sub-allocating.

If you have a particular implementation in mind, you can look at how its vector behaves, which is probably good enough if your planned allocation strategy is inherently platform-specific.