US 9,311,229 B2 · System and method for managing flash memory

Abstract

A system and method for flash memory management is provided. In particular, the system and methods herein provide for management of flash memory, particularly NAND flash memory, in a manner that potentially reduces the number of write/erase cycles typically experienced by a data storage device. When unsecure data records are to be written to the flash memory, the new or updated unsecure data records are stored in the first available location in the flash memory (e.g. a block) providing a best fit for the data records. Where the data records are updates, the updated version is stored with an incremented version number to indicate that the updated version is the current version. Older versions of the data records are deleted during garbage collection. When secure data records are to be written to the flash memory, new or updated secure data records are stored in the location in the flash memory with the most available space. Any older versions of secure data records are immediately deleted.

Claims23

Dependent claims

A method of managing flash memory, the method comprising:

in flash memory comprised in a single flash memory device:
determining that a data record to be written to the flash memory is an unsecure data record;
in response to determining that the data record to be written to the flash memory is an unsecure data record:
selecting a first block of said flash memory, the first block being selected as having a best fit for said unsecure data record;
and
writing the unsecure data record to the first block of said flash memory;
and
determining that a further data record to be written to the flash memory is a secure data record;
in response to determining that the further data record to be written to the flash memory is a secure data record:
selecting a second block of said flash memory, the second block being selected as having a maximum available space for receiving the secure data record;
and
writing the secure data record to the second block of said flash memory.

9 more elements

A data storage device, comprising:

flash memory comprised in a flash memory device;
and
a processor configured to implement the method of:
determining that a data record to be written to the flash memory is an unsecure data record;
in response to determining that the data record to be written to the flash memory is an unsecure data record:
selecting a first block of said flash memory, the first block being selected as having a best fit for said unsecure data records;
and
writing the unsecure data record to the first block of said flash memory;
and
determining that a further data record to be written to the flash memory in the same flash memory device is a secure data record;
in response to determining that the further data record is a secure data record:
selecting a second block of said flash memory, the second block being selected as having a maximum available space for receiving the secure data record;
and
writing the secure data record to the second block of said flash memory.

11 more elements

A computer program product comprising a non-transitory computer-readable medium storing code which, when executed by at least a processor of a data storage device, configures said data storage device to:

in flash memory comprised in a single flash memory device:
determine that a data record to be written to the flash memory is an unsecure data record;
in response to determining that the data record to be written to the flash memory is an unsecure data record:
select a first block of said flash memory, the first block being selected as having a best fit for said unsecure data records;
and
write the unsecure data record to the first block of said flash memory;
and
determine that a further data record to be written to the flash memory in the same flash memory device is a secure data record;
in response to determining that the further data record is a secure data record:
select a second block of said flash memory, the second block being selected as having a maximum available space for receiving the secure data record;
and
write the secure data record to the second block of said flash memory.

9 more elements

Dependencies are inferred from the claim text.

System and method for managing flash memory

Life of this patent

System and method for managing flash memory

Life of this patent

Abstract

Claims23