A GC with segregated allocations using D's static foreach.
Ceiling to closest to size class of sz.
< Page size in bytes. Linux $(shell getconf PAGESIZE).
< Size of word type (size_t).
Small slot sizes classes (in bytes).
Small page storing slots of size sizeClass.
Small pool of pages.
All small pools.
Small slot foreach slot contains wordCount machine words.
Medium slot sizes classes (in bytes).