Arena Allocator

An implementation of the Arena Allocator in C and C++.

Why Arena Allocator?

Advantages:

• Very fast allocation
• No per-allocation heap overhead
• Easy bulk deallocation through reset

Tradeoffs:

• Individual allocations cannot be freed
• Memory is reclaimed all at once

Essentially reserves a whole block of memory and just uses pointer arithmetic rather than new allocations each call. This makes it much more efficient.

Project Structure

├── c
│   ├── examples
│   │   └── main.c
│   ├── include
│   │   └── arena.h
│   ├── Makefile
│   ├── src
│   │   └── arena.c
│   └── tests
│       └── test_arena.c
├── c++
│   ├── arena_example
│   ├── arena_test
│   ├── examples
│   │   └── main.cpp
│   ├── include
│   │   └── arena.h
│   ├── Makefile
│   ├── src
│   │   └── arena.cpp
│   └── tests
│       └── test_arena.cpp
└── README.md

Building and running

To build the arena file with my example, in either C or C++ directory:

make

You can also run the tests I made:

make test

Example usage:

Arena arena(1024);

void* ptr = arena.alloc(64);

arena.reset();