because cache_mem (Config.memMaxSize) is size_t.
/* Limits and statistics */
/// the total number of shared memory bytes that can be in use at any time
-uint64_t Limit();
+size_t Limit();
/// approximate total number of shared memory bytes used now
-uint64_t Level();
+size_t Level();
/// approximate total number of shared memory bytes we can allocate now
-inline uint64_t Available() { return Limit() - Level(); }
+inline size_t Available() { return Limit() - Level(); }
/// returns page size in bytes; all pages are assumed to be the same size
size_t PageSize();