Currently refcnt map will only store the refcnt of block object held by clients. Refcnt object may delete the block object (refcnt may dec to 0) from the global cache object when all clients exit (or, more generally, when a client that has just updated the global object and exits). If another client pull the global object, it may get a block object that is already deleted by refcnt map.
Describe your problem
Currently refcnt map will only store the refcnt of block object held by clients. Refcnt object may delete the block object (refcnt may dec to 0) from the global cache object when all clients exit (or, more generally, when a client that has just updated the global object and exits). If another client pull the global object, it may get a block object that is already deleted by refcnt map.