Patents by Inventor Sampath Raja Murthy

Sampath Raja Murthy has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 12229403
    Abstract: Aspects of a storage device are provided that handle host commands associated with active and inactive zones using a hybrid L2P mapping system. The storage device includes a NVM, a controller, a first volatile memory and a second volatile memory. The controller allocates, as a superblock, one or more physical blocks respectively in one or more memory dies of the NVM, receives write commands including logical addresses associated with active zones, and stores in an L2P mapping table L2P address mappings of these logical addresses to physical addresses associated with either volatile memory or the superblock. The controller refrains from storing L2P address mappings for inactive zones, instead storing in a superblock mapping table a mapping of superblocks to inactive zones in response to respective zone finish commands. As a result, L2P mapping table sizes are reduced, zone read, reset, and TTR performance are increased, and reduced WAF is achieved.
    Type: Grant
    Filed: September 20, 2022
    Date of Patent: February 18, 2025
    Assignee: SANDISK TECHNOLOGIES, INC.
    Inventors: Chaitanya Kavirayani, Vineet Agarwal, Sampath Raja Murthy, Aakar Deora, Varun Singh
  • Patent number: 10915475
    Abstract: Aspects of the disclosure provide for management of a flash translation layer (FTL) for a non-volatile memory (NVM) in a Solid State Drive (SSD). The methods and apparatus provide a logical to physical (L2P) table where a first portion of the table is used for mapping frequently accessed hot data to a first subdrive in the NVM. Additionally, a second portion of the L2P table is provided for mapping cold data less frequently accessed than the hot data to a second subdrive, where logical blocks for storing the cold data in the second subdrive are larger than logical blocks storing the hot data in the first subdrive. Separation of the L2P table into hot and cold subdrives reduces the L2P table size that is needed in RAM for logical to physical memory mapping, while at the same time provides lower write amplification and latencies, especially for large capacity SSDs.
    Type: Grant
    Filed: October 12, 2017
    Date of Patent: February 9, 2021
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Rishabh Dubey, Saugata Das Purkayastha, Chaitanya Kavirayani, Sampath Raja Murthy, Nitin Gupta, Revanasiddaiah Prabhuswamy Mathada
  • Patent number: 10572391
    Abstract: Aspects of the disclosure provide for managing a logical to physical (L2P) table in a Solid State Drive (SSD). Methods and apparatus provide for using a non-volatile memory (NVM) to store the L2P table in its entirety, where the L2P table is separated into a plurality of partitions. The SSD is partitioned into front and back-end processing portions where a partition table is managed by the back-end portion and includes one or more addresses of partitioned portions of the plurality partitions of the L2P table stored in the NVM. The back-end processing portion receives requests from the host via the front-end processing portion and accesses the partition table for scheduling read or write access to the NVM by determining one or more addresses of the respective partitioned portions of the plurality partitions of the L2P table stored in the NVM from the partition table.
    Type: Grant
    Filed: February 9, 2018
    Date of Patent: February 25, 2020
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: Anshul Modi, Chaitanya Kavirayani, Rishabh Dubey, Sampath Raja Murthy, Satish Kumar, Vijay Sivasankaran
  • Publication number: 20190251039
    Abstract: Aspects of the disclosure provide for managing a logical to physical (L2P) table in a Solid State Drive (SSD). Methods and apparatus provide for using a non-volatile memory (NVM) to store the L2P table in its entirety, where the L2P table is separated into a plurality of partitions. The SSD is partitioned into front and back-end processing portions where a partition table is managed by the back-end portion and includes one or more addresses of partitioned portions of the plurality partitions of the L2P table stored in the NVM. The back-end processing portion receives requests from the host via the front-end processing portion and accesses the partition table for scheduling read or write access to the NVM by determining one or more addresses of the respective partitioned portions of the plurality partitions of the L2P table stored in the NVM from the partition table.
    Type: Application
    Filed: February 9, 2018
    Publication date: August 15, 2019
    Inventors: Anshul Modi, Chaitanya Kavirayani, Rishabh Dubey, Sampath Raja Murthy, Satish Kumar, Vijay Sivasankaran
  • Publication number: 20190114272
    Abstract: Aspects of the disclosure provide for management of a flash translation layer (FTL) for a non-volatile memory (NVM) in a Solid State Drive (SSD). The methods and apparatus provide a logical to physical (L2P) table where a first portion of the table is used for mapping frequently accessed hot data to a first subdrive in the NVM. Additionally, a second portion of the L2P table is provided for mapping cold data less frequently accessed than the hot data to a second subdrive, where logical blocks for storing the cold data in the second subdrive are larger than logical blocks storing the hot data in the first subdrive. Separation of the L2P table into hot and cold subdrives reduces the L2P table size that is needed in RAM for logical to physical memory mapping, while at the same time provides lower write amplification and latencies, especially for large capacity SSDs.
    Type: Application
    Filed: October 12, 2017
    Publication date: April 18, 2019
    Inventors: Rishabh Dubey, Saugata Das Purkayastha, Chaitanya Kavirayani, Sampath Raja Murthy, Nitin Gupta, Revanasiddaiah Prabhuswamy Mathada