We use a buffer pool to hold buffers uses during I/O (i.e. sending and receiving message). Using a buffer pool helps reduce the amount of work the garbage collection must do.

We currently have a single static ByteBufferFactory which gets its chunks from exactly one kind of pool, a BsonChunkPool.

It would be good to abstract the notion of a buffer pool to an interface to enable us to have multiple implementations.

This interface could look like:

public interface IBsonChunkSource : IDisposable
{
    IBsonChunk GetChunk(int requestedSize);
}

What are actually pooled are chunks, not entire buffers, which are made up of multiple chunks.

I think it's better that the name of the interface not include the word "Pool", since the source may or may not involve a pool.