Patents by Inventor Timothy J. Fisher

Timothy J. Fisher 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: 10115472
    Abstract: A data storage system includes a non-volatile memory array controlled by a controller. In response to receipt of write data to be written to the non-volatile memory array, the controller determines whether a read count of an unfinalized candidate block of storage within the non-volatile memory array satisfies a read count threshold applicable to the block. In response to determining that the read count of the unfinalized candidate block satisfies the read count threshold, the controller finalizing programming of the candidate block and programming an alternative block with the write data.
    Type: Grant
    Filed: August 2, 2017
    Date of Patent: October 30, 2018
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Camp, Timothy J. Fisher, Thomas J. Griffin, Thomas Mittelholzer, Nikolaos Papandreou, Thomas Parnell, Roman Pletka, Charalampos Pozidis, Gary A. Tressler, Sasa Tomic
  • Patent number: 10101931
    Abstract: Read errors following programming in a multi-level non-volatile memory are mitigated by a controller of the non-volatile memory. The controller temporarily buffers, in a cache, pages of data programmed into the non-volatile memory. In response to receiving a read request for a target page of data programmed into the non-volatile memory, where the read request is received during a delay time affecting the target page, the controller services the read request by accessing data of the target page in the cache in response to the read request hitting in the cache. The controller instead services the read request from the non-volatile memory in response to the read request missing in the cache. When servicing the read request from the non-volatile memory, the controller preferably reads the target page from the non-volatile memory utilizing a set of read voltage thresholds determined based on the read-after-write delay.
    Type: Grant
    Filed: June 4, 2017
    Date of Patent: October 16, 2018
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Camp, Timothy J. Fisher, Aaron D. Fry, Nikolas Ioannou, Thomas Mittelholzer, Nikolaos Papandreou, Thomas Parnell, Roman Pletka, Charalampos Pozidis, Sasa Tomic
  • Patent number: 10082962
    Abstract: In at least one embodiment, a controller of a non-volatile memory array including a plurality of subdivisions stores write data within the non-volatile memory array utilizing a plurality of block stripes of differing numbers of blocks, where all of the blocks within each block stripe are drawn from different ones of the plurality of subdivisions. The controller builds new block stripes for storing write data from blocks selected based on estimated remaining endurances of blocks in each of the plurality of subdivisions.
    Type: Grant
    Filed: November 24, 2017
    Date of Patent: September 25, 2018
    Assignee: International Business Machines Corporation
    Inventors: Timothy J. Fisher, Aaron D. Fry, Nikolas Ioannou, Ioannis Koltsidas, Jason Ma, Roman A. Pletka, Lincoln T. Simmons, Sasa Tomic
  • Patent number: 10078582
    Abstract: A method, according to one embodiment, includes assigning data having a first heat to a first data stream, assigning data having a second heat to a second data stream, and writing the data streams in parallel to page-stripes having a same index across a series of planes of memory. Other systems, methods, and computer program products are described in additional embodiments.
    Type: Grant
    Filed: December 10, 2014
    Date of Patent: September 18, 2018
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Camp, Timothy J. Fisher, Aaron D. Fry, Nikolas Ioannou, Ioannis Koltsidas, Roman Pletka, Sasa Tomic
  • Publication number: 20180196604
    Abstract: A storage system includes a controller connected to a solid state memory device. The controller releases the physical address for reassignment when no pending reads are associated with the physical address. In certain embodiments, a read status table may be included within the storage system. In certain embodiments, subsequent to the release of the physical address, erase operations may erase data at the physical address and the physical address may be reassigned to a new logical address by ensuing host write operations.
    Type: Application
    Filed: March 5, 2018
    Publication date: July 12, 2018
    Inventors: Charles J. Camp, Timothy J. Fisher, Kevin E. Sallese
  • Patent number: 10013169
    Abstract: Deduplication of data on a set of non-volatile memory by performing the following operations: receiving a first dataset; determining whether the first dataset is already present in data written to a first set of non-volatile memory; and on condition that the first dataset is determined to have already been present in the data written to the first set of non-volatile memory, providing a linking mechanism to associate the received first dataset with the already present data written to the first set of non-volatile memory.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: July 3, 2018
    Assignee: International Business Machines Corporation
    Inventors: Timothy J. Fisher, Nikolas Ioannou, Ioannis Koltsidas, Roman A. Pletka, Sasa Tomic
  • Patent number: 9996266
    Abstract: A storage system includes a memory controller connected to a solid state memory device and a read status table that tracks a pending read from the solid state memory device and a physical address of the solid state memory device that is associated with the pending read. The memory controller releases the physical address for reassignment when the read status table indicates that no pending reads are associated with the physical address. In certain embodiments, the read status table may be included within the memory controller. In certain embodiments, subsequent to the release of the physical address, erase operations may erase data at the physical address and the physical address may be reassigned to a new logical address by ensuing host write operations.
    Type: Grant
    Filed: October 24, 2017
    Date of Patent: June 12, 2018
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Camp, Timothy J. Fisher, Kevin E. Sallese
  • Patent number: 9971517
    Abstract: A method, according to one embodiment, includes: receiving a recirculation command; performing a coarse page lookup to determine valid ones of logical pages to be recirculated; requesting performance of a fine page lookup on source physical addresses containing the valid logical pages to verify the valid logical pages; and sending write commands corresponding to verified valid logical pages from the fine page lookup. Other systems, methods, and computer program products are described in additional embodiments.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: May 15, 2018
    Assignee: International Business Machines Corporation
    Inventors: Timothy J. Fisher, Lincoln T. Simmons, Adalberto G. Yanes
  • Publication number: 20180121094
    Abstract: In at least one embodiment, a controller of a non-volatile memory array including a plurality of subdivisions stores write data within the non-volatile memory array utilizing a plurality of block stripes of differing numbers of blocks, where all of the blocks within each block stripe are drawn from different ones of the plurality of subdivisions. The controller builds new block stripes for storing write data from blocks selected based on estimated remaining endurances of blocks in each of the plurality of subdivisions.
    Type: Application
    Filed: November 24, 2017
    Publication date: May 3, 2018
    Inventors: TIMOTHY J. FISHER, AARON D. FRY, NIKOLAS IOANNOU, IOANNIS KOLTSIDAS, JASON MA, ROMAN A. PLETKA, LINCOLN T. SIMMONS, SASA TOMIC
  • Patent number: 9946594
    Abstract: A flash memory codeword architecture is provided. A non-integer count of logical pages is packed into a codeword payload data container. A codeword payload header is generated. The codeword payload header includes an offset to a first logical page that is packed, at least in part, into the codeword payload data container. The codeword payload data container and the codeword payload header are concatenated to generate a codeword payload. Error-correcting code data is generated based, at least in part, on the codeword payload using a systematic error-correcting code. The codeword payload and error-correcting code data is concatenated to generate a codeword. A physical page is programmed with the codeword.
    Type: Grant
    Filed: August 19, 2015
    Date of Patent: April 17, 2018
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Camp, Timothy J. Fisher, Aaron D. Fry, Lincoln T. Simmons, Adalberto G. Yanes
  • Patent number: 9940034
    Abstract: A mechanism is provided in a non-volatile memory controller for reducing read access latency by straddling pages across non-volatile memory channels. Responsive to a request to write a logical page to a non-volatile memory array, the non-volatile memory controller determines whether the logical page fits into a current physical page. Responsive to determining the logical page does not fit into the current physical page, the non-volatile memory controller writes a first portion of the logical page to a first physical page in a first block and writes a second portion of the logical page to a second physical page in a second block. The first physical page and the second physical page are on different non-volatile memory channels.
    Type: Grant
    Filed: January 25, 2016
    Date of Patent: April 10, 2018
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Camp, Timothy J. Fisher, Aaron D. Fry, Nikolas Ioannou, Thomas Parnell, Roman Pletka, Sasa Tomic
  • Patent number: 9928166
    Abstract: Decisions about how to correlate logical address to physical addresses in a flash memory (or other non-volatile random access memory) is based at least in part upon how frequently a logical address is accessed over time. Accordingly, software tracks accesses, by logical address, to the stored data using a flash memory metadata structure, and calculates a frequency-of-access value for each logical address of the set of logical addresses corresponding to the relative frequency with which the corresponding logical address is accessed, based, at least in part, on the flash memory metadata structure. For example, logical addresses with low frequency may be grouped together so that the frequency of erasure operations (which are often done on a block by block basis) will tend to be reduced.
    Type: Grant
    Filed: December 24, 2013
    Date of Patent: March 27, 2018
    Assignee: International Business Machines Corporation
    Inventors: Timothy J. Fisher, Aaron D. Fry
  • Publication number: 20180081765
    Abstract: A controller-implemented method, according to one embodiment, includes: examining, by the controller, each of a plurality of journal entries from at least one journal beginning with a most recent one of the journal entries in a most recent one of the at least one journal and working towards an oldest one of the journal entries in an oldest one of the at least one journal, the journal entries corresponding to one or more updates made to one or more logical to physical table (LPT) entries of a LPT; determining, by the controller, whether a current LPT entry, which corresponds to a currently examined journal entry, has already been updated; and discarding, by the controller, the currently examined journal entry in response to determining that the current LPT entry has already been updated.
    Type: Application
    Filed: November 28, 2017
    Publication date: March 22, 2018
    Inventors: Charles J. Camp, Timothy J. Fisher, Aaron D. Fry, Nikolas Ioannou, Roman A. Pletka, Lincoln T. Simmons, Sasa Tomic
  • Publication number: 20180081752
    Abstract: Techniques for data deduplication in a data storage system include comparing a first attribute of a received data page to first attributes of one or more stored data pages. In response to the first attribute matching one of the first attributes, a second attribute of the received data page is compared to second attributes of the one or more data pages. In response to the second attribute of the received data page matching one of the second attributes, a fingerprint of the received data page is compared to fingerprints of the one or more data pages. In response to the fingerprint of the received data page matching one of the fingerprints, the received data page is discarded and replaced with a reference to the corresponding data page already stored in the storage system. In response to first attribute, the second attribute, or the fingerprint of the received data page not matching, the received data page is stored.
    Type: Application
    Filed: November 28, 2017
    Publication date: March 22, 2018
    Inventors: TIMOTHY J. FISHER, NIKOLAS IOANNOU, THOMAS PARNELL, ROMAN A. PLETKA, SASA TOMIC
  • Publication number: 20180059940
    Abstract: A computer program product according to one embodiment includes a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processing circuit to cause the circuitry to perform a method including determining, after writing data to a non-volatile memory block, one or more delta threshold voltage shift (TVS?) values. One or more overall threshold voltage shift values for the data written to the non-volatile memory block are calculated, the values being a function of the one or more TVS? values to be used when writing data to the non-volatile memory block. The overall threshold voltage shift values are stored. A base threshold voltage shift (TVSBASE) value, the one or more TVS? values, or both the TVSBASE value and the one or more TVS? values are re-calibrated during a background health check after a predetermined number of background health checks without calibration are performed.
    Type: Application
    Filed: November 6, 2017
    Publication date: March 1, 2018
    Inventors: Charles J. Camp, Timothy J. Fisher, Aaron D. Fry, Nikolas Ioannou, Ioannis Koltsidas, Nikolaos Papandreou, Thomas Parnell, Roman A. Pletka, Charalampos Pozidis, Sasa Tomic
  • Publication number: 20180059941
    Abstract: In one embodiment, a computer program product includes a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processing circuit to cause the processing circuit to perform a method that includes determining, after writing data to a non-volatile memory block, one or more delta threshold voltage shift (TVS?) values. One or more overall threshold voltage shift values is calculated for the data written to the non-volatile memory block. The one or more overall threshold voltage shift values are stored. The method also includes reading one or more TVS values from a non-volatile controller memory, and resetting a program/erase cycle count since last calibration after calibrating the one or more overall threshold voltage shift values. The one or more TVS? values and the program/erase cycle count since last calibration are stored to the non-volatile controller memory.
    Type: Application
    Filed: November 6, 2017
    Publication date: March 1, 2018
    Inventors: Charles J. Camp, Timothy J. Fisher, Aaron D. Fry, Nikolas Ioannou, Ioannis Koltsidas, Nikolaos Papandreou, Thomas Parnell, Roman A. Pletka, Charalampos Pozidis, Sasa Tomic
  • Patent number: 9904607
    Abstract: A controller-implemented method, according to one embodiment, includes: restoring a valid snapshot of a LPT from the non-volatile random access memory, examining each journal entry from at least one journal beginning with a most recent one of the journal entries in a most recent one of the at least one journal and working towards an oldest one of the journal entries in an oldest one of the at least one journal, the journal entries corresponding to updates made to one or more entries of the LPT, determining whether a current LPT entry which corresponds to a currently examined journal entry has already been updated, using the currently examined journal entry to update the current LPT entry in response to determining that the current LPT entry has not already been updated, and discarding the currently examined journal entry in response to determining that the current LPT entry has already been updated.
    Type: Grant
    Filed: November 13, 2015
    Date of Patent: February 27, 2018
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Camp, Timothy J. Fisher, Aaron D. Fry, Nikolas Ioannou, Roman A. Pletka, Lincoln T. Simmons, Sasa Tomic
  • Patent number: 9898215
    Abstract: In at least one embodiment, a non-volatile memory array including a plurality of blocks each including a plurality of physical pages is controlled by a controller. The controller implements a plurality of nested page retirement classes each defined by a respective one of a plurality of different nested subsets of page indices of physical pages within the plurality of blocks that are to be considered retired from use. For each block among the plurality of blocks, the controller updating an indication of a page retirement class to which the block belongs in response to detection of a retirement-causing error in a data page stored in a physical page of the block. The controller forms block stripes for storing data from the plurality of blocks based on the page retirement classes of the blocks.
    Type: Grant
    Filed: December 7, 2015
    Date of Patent: February 20, 2018
    Assignee: International Business Machines Corporation
    Inventors: Charles J. Camp, Timothy J. Fisher, Nikolas Ioannou, Thomas Parnell, Roman A. Pletka, Sasa Tomic
  • Publication number: 20180046377
    Abstract: A storage system includes a memory controller connected to a solid state memory device and a read status table that tracks a pending read from the solid state memory device and a physical address of the solid state memory device that is associated with the pending read. The memory controller releases the physical address for reassignment when the read status table indicates that no pending reads are associated with the physical address. In certain embodiments, the read status table may be included within the memory controller. In certain embodiments, subsequent to the release of the physical address, erase operations may erase data at the physical address and the physical address may be reassigned to a new logical address by ensuing host write operations.
    Type: Application
    Filed: October 24, 2017
    Publication date: February 15, 2018
    Inventors: Charles J. Camp, Timothy J. Fisher, Kevin E. Sallese
  • Publication number: 20180039536
    Abstract: A computer-implemented method, according to one embodiment, includes: detecting at least one read of a logical page straddled across codewords, storing an indication of a number of detected reads of the straddled logical page, and relocating the straddled logical page to a different physical location in response to the number of detected reads of the straddled logical page. When relocated, the logical page is written to the different physical location in a non-straddled manner. Other systems, methods, and computer program products are described in additional embodiments.
    Type: Application
    Filed: October 19, 2017
    Publication date: February 8, 2018
    Inventors: Charles J. Camp, Timothy J. Fisher, Nikolas Ioannou, Thomas Parnell, Roman A. Pletka, Sasa Tomic