Intel Corporation
Read quality of service for non-volatile memory

Abstract:

A method and apparatus to reduce read latency and improve read quality of service (Read QoS) for non-volatile memory, such as NAND array in a NAND device. For read commands that collide with an in-progress program array operation targeting the same program locations in a NAND array, the in-progress program is suspended and the controller allows the read command to read from the internal NAND buffer instead of waiting for the in-progress program to complete. For read commands queued during an in-progress program that is processing pre-reads in preparation for a program array operation, pre-read bypass allows the reads to be serviced between the pre-reads and before the program's array operation starts. In this manner, read commands can be serviced without suspending the in-progress program. Allowing internal NAND buffer reads and enabling pre-read bypass reduces read latency and improves Read QoS.