NewGlobalMap creates a globalMap.

GlobalCachedMap keeps a global map of objects that can be looked up in thread-local cache The objects can only be added, never removed or replaced, because their references are copied to local cache for fast access.

LocalCachedMap keeps local cache of global map for fast access, unprotected by mutex.

GlobalObjectConstructor defines a function that creates a new global item in GlobalCachedMap.

GlobalObjectDestructor defines a function that destroys a global item in GlobalCachedMap.

LocalWrapperConstructor defines a function that creates a local wrapper for a global item in GlobalCachedMap.