Accessing compressed data of varying-sized quanta in non-volatile memory

Abstract

Accessing data of varying-sized quanta in non-volatile memory provides improved storage efficiency in some situations. For example, a Solid-State Disk (SSD) controller receives (e.g. uncompressed) data from a computing host (e.g. a disk write command), compresses the data, and stores the compressed data into non-volatile (e.g. flash) memory. In response to a subsequent request from the host (e.g. a disk read command), the SSD controller reads and uncompresses the compressed data from the memory. The compressed data is stored in the memory according to varying-sized quanta, due to, e.g., compression algorithm, operating mode, and compression effectiveness on various data. The SSD controller uncompresses the data in part by consulting an included map table to locate header(s) stored in the memory, parsing the header(s) to locate appropriate (compressed) data stored in the memory, and uncompressing the appropriate data from the memory to produce the uncompressed data.