SYSTEM AND METHOD FOR EFFICIENT FLASH TRANSLATION LAYER

• US 20150149706A1
• Filed: 09/09/2014
• Published: 05/28/2015
• Est. Priority Date: 11/27/2013
• Status: Active Grant

• Current Assignee: NGD Systems, Inc.
• Original Assignee: NxGn Data, Inc.
• Inventors: Salessi, Nader, Alcantara, Joao
• Granted Patent: US 9,348,760 B2
• Time in Patent Office: Days
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/1009 using page tables, e.g. page table structures
• CPC Class Codes: G06F 2212/65 Details of virtual memory and virtual address translation
• CPC Class Codes: G06F 2212/7201 Logical to physical mapping or translation of blocks or pages

Abstract

A method of maintaining and updating a logical-to-physical (LtoP) table in a storage device including a processor, a volatile memory, and a non-volatile memory, the storage device being in communication with a host, the method including receiving, by the processor, data for storing at a physical address in the non-volatile memory, the data being associated with a logical address of the host, storing, by the processor, the physical address in a first LtoP zone of a plurality of LtoP zones of the LtoP table, the LtoP table being stored in the volatile memory, adding, by the processor, the first LtoP zone to a list of modified zones, and storing, by the processor, a second LtoP zone of the plurality of LtoP zones in the non-volatile memory when a size of the list of modified zones exceeds a threshold.

Claims

1. A method of maintaining and updating a logical-to-physical (LtoP) table in a storage device comprising a processor, a volatile memory, and a non-volatile memory, the storage device being in communication with a host, the method comprising:

receiving, by the processor, data for storing at a physical address in the non-volatile memory, the data being associated with a logical address of the host;

storing, by the processor, the physical address in a first LtoP zone of a plurality of LtoP zones of the LtoP table, the LtoP table being stored in the volatile memory;

adding, by the processor, the first LtoP zone to a list of modified zones;

storing, by the processor, a second LtoP zone of the plurality of LtoP zones in the non-volatile memory when a size of the list of modified zones exceeds a threshold; and

after the receiving of the data, storing, by the processor, the data at a physical address in the non-volatile memory,

wherein at least one physical address is stored in each LtoP zone of the plurality of LtoP zones.

2. A method of maintaining and updating a logical-to-physical (LtoP) table in a storage device comprising a processor, a volatile memory, and a non-volatile memory, the storage device being in communication with a host, the method comprising:

receiving, by the processor, data for storing at a physical address in the non-volatile memory, the data being associated with a logical address of the host;

storing, by the processor, the physical address in a first LtoP zone of a plurality of LtoP zones of the LtoP table, the LtoP table being stored in the volatile memory;

adding, by the processor, the first LtoP zone to a list of modified zones; and

storing, by the processor, a second LtoP zone of the plurality of LtoP zones in the non-volatile memory when a size of the list of modified zones exceeds a threshold,

wherein the storing of the second LtoP zone in the non-volatile memory comprises storing the second LtoP zone in a data structure comprising a zone number and a zone information, and wherein the size of the list of modified zones is equal to a number of LtoP zones of the plurality of LtoP zones added to the list of modified zones.

3. A method of maintaining and updating a logical-to-physical (LtoP) table in a storage device comprising a processor, a volatile memory, and a non-volatile memory, the storage device being in communication with a host, the method comprising:

receiving, by the processor, data for storing at a physical address in the non-volatile memory, the data being associated with a logical address of the host;

storing, by the processor, the physical address in a first LtoP zone of a plurality of LtoP zones of the LtoP table, the LtoP table being stored in the volatile memory;

adding, by the processor, the first LtoP zone to a list of modified zones;

storing, by the processor, a second LtoP zone of the plurality of LtoP zones in the non-volatile memory when a size of the list of modified zones exceeds a threshold; and

after the storing of the second LtoP zone, removing the second LtoP zone from the list of modified zones,

wherein zones of the plurality of LtoP zones are contiguous and sequential, and

wherein each LtoP zone of the plurality of LtoP zones is 4 KB in size.