fn extent_classes(page: usize) -> Vec<usize>Available on Unix and crate feature
pool only.Expand description
The extent size-class ladder for a page-byte page size: page, then
sizes of the form 2^k and 3 * 2^(k-1) bytes, up through the first
class that fits max_stored_len, the codec contract’s worst case,
over the largest chunk size class. Every class is a multiple of page
(the sub-page mid class between page and 2 * page is skipped), so
slot-granular paging advice is exact on any kernel page size.
Consecutive classes above the smallest are within 1.5x of each other,
which bounds a stored payload’s internal fragmentation below 1.5x
(page-granular slack at the small end).