or ‘small’ buffers ▸ … to reduce internal fragmentation ▸ Tiny – 32, 64, 96, 128, … 512 bytes ▸ Small – 1024, 2048, 4096 bytes ▸Uses a leaf node of a chunk – i.e. a 8192-byte block ▸Arena keeps the linked lists of PoolSubpages ▸ … so that it doesn’t need to traverse deep to the leaf level. ▸ Each size has its own linked list and lock ▸ 16 for tiny and 3 for small PoolSubpage