Write and retire pages in QLC NAND blocks

An integrated QLC NAND flash memory system for writing data to pages in a QLC block of said QLC NAND flash memory device, said device comprising a plurality of SLC pages organized in SLC blocks and a plurality of QLC pages organized in QLC blocks, said system comprising:

• one or more processors and a memory operatively coupled to said one or more processors, wherein said memory stores program code portions which, when executed by said one or more processors, enable said one or more processors to;
• store received data in SLC pages,
• divide equally a QLC block in a predefined number of sub-blocks according to a corresponding QLC page health status of said pages of said QLC block, and
• upon determining that SLC pages are to be copied from SLC pages to QLC pages;
• copy device-internal said respective SLC pages to said sub-blocks of
• said QLC block using device-internal cache registers,
• wherein said copying is based on an error-count aware scheme.

A computer program product for writing data to pages in a QLC block of said QLC NAND flash memory device, said device comprising a plurality of SLC pages organized in SLC blocks and a plurality of QLC pages organized in QLC blocks, said computer program product comprising a computer readable storage medium having program instructions embodied therewith, said program instructions being executable by one or more computing systems or controllers to cause said one or more computing systems to:

• store received data in SLC pages,
• divide equally a QLC block in a predefined number of sub-blocks according to a corresponding QLC page health status of said pages of said QLC block, and
• upon determining that SLC pages are to be copied from SLC pages to QLC pages copy device-internal said respective SLC pages to said sub-blocks of
• said QLC block using device-internal cache registers,
• wherein said copying is based on an error-count aware scheme.