Abstract: A method for operating a non-volatile memory is provided. The non-volatile memory includes a plurality of physical blocks haing a plurality of data blocks and spare blocks. An index is obtained by comparing an average erase count of selected physical blocks with a first threshold. Each erase count for each physical block is the total number of the erase operations performed thereon. A performance capability status for the memory is determined according to the index. The performance capability status is set to a first status when the average erase count exceeds the first threshold. An indication is generated based on the performance capability status. A limp function is performed in response to the first status for configuring a minimum number of the at least some spare blocks reserved and used for data update operations.