Write your own memory manager [closed]

Question

I'd like to write my own memory manager. The target language is C++ and the goal of the memory manager is mainly to help debugging. It should detect double frees, memory overwrite and so on. And of course - I'd like to learn about memory management.

Can someone give me a hint so resources where I can learn how to write such a memory manager?

Thank you for your help.

Answer 1

I think this is a very interesting project that you might learn a lot from. Here's a little bit of reading material on the subject of memory management. It goes over some of the basics of memory management, leads into a simple malloc implementation, then touches on a couple more advanced topics.

Inside memory management

Also, since you mention that you want to make a memory manager that is useful for debugging, you may want to consider reading this paper by the developers of Memcheck/Valgrind (A wonderful memory debugger for Linux). It details how they track all the the metadata (whether or not a particular byte is defined, intialized, etc.) in memchck. It's a bit detailed, but it's good reading on how to make a scalable and efficient dynamic memory checker.

How to Shadow Every Byte of Memory Used by a Program

Answer 2

Dave Hanson's C Interfaces and Implementations presents first a standard memory manager and then a memory manager with a few debugging features. This would be a great starting point to learn from and extend.

Of course, if you actually want to diagnose memory problems in a running C or C++ program, you should use valgrind.