Object Object Pool

A manual memory management tool for JavaScript.

Why?

Sometimes you have a lot of objects. Sometimes having those garbage collect causes some sawtooth ugliness

OK but why is this bad?

Garbage collection can be slow, especially if you're working with a lot of objects. Sometimes it is better to allocate a bunch of objects you need and just reuse them. see this dope article

API

The API for this is fairly simple and straight forward. You have an alloc() method, a free(object) method, and a collect() method available.

constructor

the constructor for an ObjectPool has an optional number of objects you can give it. If you pass a number, it will preallocate that many objects.

let pool = new ObjectPool();
console.log(pool.status.totalAllocated);
// 0

let poolPreAlloc = new ObjectPool(5);
console.log(pool.status.totalAllocated);
// 5

The following all assume you have created an object pool.

let pool = new ObjectPool();

alloc()

This will assign myObject to be {}. You can use this object as you wish. When you are done with this obect you can free it.

console.log(pool.status.totalAllocated)
// 0

let myObject = pool.alloc();
// {}
console.log(pool.status.totalAllocated)
// 1
console.log(pool.status.totalFree)
// 0

free()

When you are finished with an object, calling pool.free(object) will mark it as free to use again. When you do this, you should also mark your reference to the object as null.

let myObject = pool.alloc();
// {}
console.log(pool.status.totalAllocated)
// 1
console.log(pool.status.totalFree)
// 0
pool.free(myObject); // internally recycles object
myObject = null;
console.log(pool.status.totalAllocated)
// 1
console.log(pool.status.totalFree)
// 1

collect()

collect() will remove all unused objects from your pool. If you have allocated 5 objects, and one is in use, internally you will have one allocated object and zero free objects.

let objectOne = pool.alloc();
let objectTwo = pool.alloc();

console.log(pool.status.totalAllocated);
// 2
console.log(pool.status.totalFree);
// 0

pool.free(objectTwo); // internally recycles object
objectTwo = null;

console.log(pool.status.totalAllocated)
// 2
console.log(pool.status.totalFree)
// 1

pool.collect();

console.log(pool.status.totalAllocated)
// 1
console.log(pool.status.totalFree)
// 0