Abstract: A method and system for folding only a portion of data from an SLC block to an MLC block is described. The method includes identifying word lines with only valid data and word lines with non-valid data in a selected SLC block, copying data only from word lines with valid data to a destination MLC block and copying data from word lines in the selected SLC block with non-valid data to a separate SLC compaction block. The system includes a first controller module configured to scan for word lines with only valid data and pass only a bitmap regarding valid and invalid word lines to a second controller module. The second controller module is configured to perform on-chip folding of data from valid word lines, and to copy data from invalid data word lines to an SLC compaction block.

Abstract: A storage module may be configured to organize data to be moved from an initial storage location to a destination storage location into sets, and to determine whether to commit the data to the destination storage location on a set-by-set basis. Error correction and/or a post write and read process may be performed on the sets that are copied to the destination storage location to determine whether to commit each of the copied sets.