PostgreSQL Allocates Memory Fast
Every C program that wants to be fast needs to be fast at allocating memory. PostgreSQL allocates memory in the tightest loop imaginable: a hash join probes its hash table once per …
Memory
tmux Stores Grid Cells in Five Bytes
tmux splits a grid cell into two representations: a fat 32-byte in-memory form and a packed 5-byte stored form.
CPython Reuses Objects with Free Lists: Recycling Dead Objects for Free
Freelists turn the first word of a dead object into a linked-list pointer, so the next list, tuple, or float pops a ready-made shell instead of hitting the allocator.
CPython's Pymalloc: A Fast Allocator for Small Objects
Pymalloc hands out small objects in a few instructions: one array lookup, one comparison, one free-list pop — and a radix tree that answers ‘is this pointer mine?’ in O(1).