Rajiv O Agarwal

US Patent:

8185787, May 22, 2012

Filed:

Apr 8, 2009

Appl. No.:

12/384894

Inventors:

Marcus Marrow - Santa Clara CA, US
Jason Bellorado - Santa Clara CA, US
Rajiv Agarwal - Palo Alto CA, US

Assignee:

Link—A—Media Devices Corporation - Santa Clara CA

International Classification:

G11C 29/00

US Classification:

714721, 714719

Abstract:

A technique for blind channel estimation is disclosed herein. A read value that is read from a multi-level storage device is received, as are a set of bins having bin ranges and (for each of the bins in the set) a corresponding portion of read values which fall into that particular bin. One or more of the bin ranges is adjusted such that the received portions of read values remain substantially the same after adjustment and after assignment of the read value to one of the set of bins after adjustment.

US Patent:

8433981, Apr 30, 2013

Filed:

Dec 2, 2010

Appl. No.:

12/959101

Inventors:

Rajiv Agarwal - Palo Alto CA, US
Marcus Marrow - Santa Clara CA, US

Assignee:

SK hynix memory solutions inc. - San Jose CA

International Classification:

G06F 11/00

US Classification:

714773

Abstract:

Data is stored from a host. A flash memory is divided into a plurality of memory groups, the memory groups each comprising a plurality of flash memory blocks. A first portion of one of the plurality of memory groups is allocated for storing parity data of an error-correcting code for the memory group. A second portion of the memory group is allocated for storing data from the host. A flash memory block in the memory group is erased prior to writing the data from the host, wherein the flash memory block contains valid data. The erased valid data is recovered using the error-correcting code.

US Patent:

8443244, May 14, 2013

Filed:

Apr 25, 2012

Appl. No.:

13/456065

Inventors:

Marcus Marrow - San Jose CA, US
Jason Bellorado - San Jose CA, US
Rajiv Agarwal - Palo Alto CA, US

Assignee:

SK hynix memory solutions inc. - San Jose CA

International Classification:

G11C 29/00
G11C 11/34

US Classification:

714721, 36518503

Abstract:

A read value that is read from a multi-level storage device is received, as are a set of bins having bin ranges. A set of amounts corresponding to the set of bins is received where each amount in the set indicates an amount of read values which fall into the corresponding bin. One or more of the bin ranges is adjusted, including by: in the event there is a first bin range that is less than the received read value, increasing at least the first bin range and in the event there is a second bin range that is greater than the received read value, decreasing at least the second bin range.

US Patent:

8447919, May 21, 2013

Filed:

Aug 4, 2010

Appl. No.:

12/806125

Inventors:

Rajiv Agarwal - Palo Alto CA, US
Marcus Marrow - Santa Clara CA, US

Assignee:

SK hynix memory solutions inc. - San Jose CA

International Classification:

G06F 12/00

US Classification:

711103, 714718

Abstract:

Flash memory is written to by determining a measure of health for each of a plurality of locations in flash memory. At least one of the plurality of locations in flash memory is selected based at least in part on the determined measures of health and the selected location(s) in flash memory is/are written to.

US Patent:

8621293, Dec 31, 2013

Filed:

Apr 16, 2013

Appl. No.:

13/864161

Inventors:

Jason Bellorado - San Jose CA, US
Rajiv Agarwal - Palo Alto CA, US

Assignee:

SK hynix memory solutions inc. - San Jose CA

International Classification:

G11C 29/00
H03M 13/00

US Classification:

714721, 714752

Abstract:

A value read back from storage and a set of bins are received. Each bin in the set of bins has a bin range. A bin corresponding to the read-back value is selected from the set of bins. The bin range of the selected bin is adjusted, based at least in part on the read-back value, so that the read-back value is more centered within the selected bin after adjustment.

US Patent:

20170262336, Sep 14, 2017

Filed:

May 25, 2017

Appl. No.:

15/604693

Inventors:

- Hopkinton MA, US
Rajiv Agarwal - Santa Clara CA, US
Jeffrey Paul Ferreira - Santa Clara CA, US
Jeffrey S. Bonwick - Santa Clara CA, US
Michael W. Shapiro - Santa Clara CA, US

International Classification:

G06F 11/10
G06F 11/22
G06F 3/06
G06F 11/07

Abstract:

A method for managing persistent storage. The method includes selecting a page for a proactive read request, where the page is located in the persistent storage. The method further includes issuing the proactive read request to the page, receiving, in response to the proactive read request, a bit error value (BEV) for data stored on the page, obtaining a BEV threshold (T) for the page, wherein T is determined using a program/erase cycle value associated with the page and a retention time of the data stored on the page, making a first determination that the BEV is greater than T, based on the first determination: identifying an m-page, where the m-page is a set of pages and the page is in the set of pages, and setting the m-page as non-allocatable for future operations.

US Patent:

20160092304, Mar 31, 2016

Filed:

Sep 30, 2014

Appl. No.:

14/501917

Inventors:

- Santa Clara CA, US
Rajiv Agarwal - Santa Clara CA, US
Jeffrey Paul Ferreira - Santa Clara CA, US
Jeffrey S. Bonwick - Santa Clara CA, US
Michael W. Shapiro - Menlo Park CA, US

International Classification:

G06F 11/10
G06F 11/07

Abstract:

A method for managing persistent storage. The method includes selecting a page for a proactive read request, where the page is located in the persistent storage. The method further includes issuing the proactive read request to the page, receiving, in response to the proactive read request, a bit error value (BEV) for data stored on the page, obtaining a BEV threshold (T) for the page, wherein T is determined using a program/erase cycle value associated with the page and a retention time of the data stored on the page, making a first determination that the BEV is greater than T, based on the first determination: identifying an m-page, where the m-page is a set of pages and the page is in the set of pages, and setting the m-page as non-allocatable for future operations.

US Patent:

20160093397, Mar 31, 2016

Filed:

Sep 30, 2014

Appl. No.:

14/501800

Inventors:

- Santa Clara CA, US
Rajiv Agarwal - Santa Clara CA, US
Michael Francis Barrientos - Santa Clara CA, US
Jeffrey Paul Ferreira - Santa Clara CA, US
Jeffrey S. Bonwick - Santa Clara CA, US
Michael W. Shapiro - Menlo Park CA, US

International Classification:

G11C 16/34
G11C 16/04

Abstract:

A method for reading data from persistent storage. The method includes receiving a client read request that includes a logical address for data from a client, determining a physical address using the logical address where the physical address includes a page number for a physical page in the persistent storage, determining a retention time for the data, determining a program/erase (P/E) cycle value associated with the physical page, obtaining at least one read threshold value using the P/E cycle value, the retention time, and the page number, issuing a control module read request including the at least one read threshold value to a storage module that includes the physical page, and obtaining the data from the physical page using the at least one read threshold value.