A request is received to access physical information of a memory unit included in a memory device. A determination is made whether the physical information is available in a physical information table present in a memory cache. If the physical information of the memory unit is available in the table, the physical information is accessed from the table. If the physical information is not available in the table, a global directory in the memory cache is accessed, which indicates locations in a non-volatile memory that store the total number of the physical information blocks. From the global directory, a particular location in the non-volatile memory storing a particular physical information block that includes the physical information of the memory unit is determined. The particular physical information block is loaded into the table and the physical information of the memory unit is accessed from the particular physical information block.