KeptFieldSets

The kept field sets of the process, by hash (field-presentation §FVK-7, §FVE-11).

In the namespace field. Declared in src/libs/libfield/field/KeptFieldSets.hpp.

Detailed description

A solve keeps the hash of each field set in the item's solve history. Construct notes the file of each kept set here, and the first reference that names `<hash>/<field>` loads it. The last kMaxLoaded sets stay loaded, the least used goes first. A set that is put() from memory, as a test does, stays until forget().

Thread-safe: the asset store's pool threads evaluate references.