FILE SYSTEM DERIVED METADATA FOR MANAGEMENT OF NON-VOLATILE MEMORY

• US 20110066789A1
• Filed: 09/16/2009
• Published: 03/17/2011
• Est. Priority Date: 09/16/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Khmelnitsky, Vadim, Post, Daniel Jeffrey, Wakrat, Nir Jacob
• Granted Patent: US 8,838,877 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 16/1727 Details of free space management performed by the file system saving storage space on storage systems G06F3/0608; management of blocks in storage devices G06F3/064
• CPC Class Codes: G06F 16/1847 specifically adapted to static storage, e.g. adapted to flash memory or SSD
• CPC Class Codes: G06F 2212/7201 Logical to physical mapping or translation of blocks or pages
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 2212/7207 management of metadata or control data
• CPC Class Codes: G06F 2212/7211 Wear leveling

Abstract

A file system programs metadata on a non-volatile memory device. The metadata can include data associating files with ranges of logical block addresses. During a garbage collection process, the data can be used to determine portions of physical blocks of the non-volatile memory device that are associated with files that have been deleted. Using the programmed metadata during garbage collection results in erasure of larger portions of blocks and improved wear leveling.

Claims

1. A method performed by a processor in a non-volatile memory system, comprising:

receiving a request for memory management;

retrieving file metadata programmed into a memory array by a file system; and

identifying blocks of non-volatile memory for memory management based on the file metadata.

2. The method of claim 1, where the memory management is one of garbage collection or wear leveling.

3. The method of claim 1, where the metadata includes a unique object identifier and one or more ranges of logical block addresses associated with the unique object identifier.

4. A method performed by a processor in a non-volatile memory system, comprising:

creating a file in a file system of a host system; and

programming a non-volatile memory array of a non-volatile memory device with metadata associated with the file, the metadata including one or more logical block addresses of non-volatile memory storing file data.

5. The method of claim 4, where the metadata includes a unique object identifier and at least one range of logical block addresses.

6. A non-volatile memory system, comprising:

a host channel coupling a host system and a non-volatile memory device, the host channel configurable for receiving a request for memory management from the host system;

a controller included in the non-volatile memory device and coupled to the host channel, the controller configurable for retrieving file metadata programmed into a memory array by a file system operated by the host system; and

identifying blocks of non-volatile memory for memory management collection based on the file metadata.

7. The system of claim 6, where the memory management is one of garbage collection or wear leveling.

8. The system of claim 6, where the metadata includes a unique object identifier and at least one range of logical block addresses.

9. A non-volatile memory system including a host system and a non-volatile memory device, the system comprising:

a processor in the host system configurable for creating a file and file metadata; and

a host channel coupling the host system and the non-volatile memory device, the host channel for programming a memory array in the non-volatile memory device with the file metadata, the file metadata including a unique object identifier and one or more ranges of logical block addresses associated with the unique object identifier.

10. The system of claim 9, comprising:

a controller in the non-volatile memory device, the controller configurable to use the file meta data for management of the memory array.

11. The system of claim 10, where management of the memory array includes one of garbage collection or wear leveling.