Patents by Inventor Luis A. Lastras

Luis A. Lastras 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).

  • Publication number: 20150212951
    Abstract: A hybrid encryption scheme for storing data lines in a memory includes identifying data lines determined to be frequently accessed, and encrypting the data lines using a first encryption scheme. The hybrid encryption scheme also includes encrypting data lines determined not to be frequently accessed using a second encryption scheme.
    Type: Application
    Filed: January 27, 2014
    Publication date: July 30, 2015
    Applicant: International Business Machines Corporation
    Inventors: Michele M. Franceschini, Ashish Jagmohan, Luis A. Lastras-Montano, Moinuddin K. A. Qureshi
  • Publication number: 20150212886
    Abstract: Error checking and correcting (ECC) may be performed in an on-chip memory where an error is corrected by a controller and not the on-chip memory. The controller may be flagged to show that an error has occurred and where it has occurred in the memory. The controller may access ECC bits associated with the error and may fix incorrect data. The error checking may be done in parallel with read operations of the memory so as to lower latency.
    Type: Application
    Filed: June 30, 2014
    Publication date: July 30, 2015
    Inventors: Paul W. Coteus, Hillery C. Hunter, Charles Arthur Kilmer, Kyu-hyoun Kim, Luis A. Lastras-Montano, Warren E. Maule, Vipinchandra Patel
  • Patent number: 9087612
    Abstract: Errors on a dynamic random access memory (“DRAM”) having an error correcting decoder (“ECC”) can be detected by the ECC when reading a row of the DRAM. The ECC includes error correcting code logic. If errors are detected that cannot be corrected by the ECC logic, test control logic determines weak cell information for the row, evaluates the errors using the weak cell information, and may correct the errors. The weak cell information may include weak cell locations and failure values.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: July 21, 2015
    Assignee: International Business Machines Corporation
    Inventors: Michele M. Franceschini, Hillery C. Hunter, Ashish Jagmohan, Charles A. Kilmer, Kyu-hyoun Kim, Luis A. Lastras-Montano, Moinuddin K. Qureshi
  • Patent number: 9071277
    Abstract: Correction of structured burst errors in data is provided by a system that includes an encoder and is configured for performing a method. The method includes receiving data that includes a plurality of subsets of data. The data is encoded by an encoder using a combination of a first error correcting code and a second error correcting code. The first error correcting code is configured to provide error recovery from a structured burst error in one of the subsets of data, the structured burst error having a length less than a specified maximum length. The second error correcting code is configured to extend the first error correcting code to provide error recovery from the structured burst error in any of the subsets of data. The encoded data is output.
    Type: Grant
    Filed: July 24, 2012
    Date of Patent: June 30, 2015
    Assignee: International Business Machines Corporation
    Inventors: Michele M. Franceschini, Luis A. Lastras-Montano
  • Patent number: 9058276
    Abstract: Channel marking is provided in a memory system that includes a memory channel with a plurality of memory devices. The memory devices are arranged into a first group of memory devices and a second group of memory devices. The memory system is configured to perform a method that includes determining that more than a threshold number of memory devices in the first group are failing. An error correction code (ECC) is configured to compensate for errors associated with memory devices in the first group on the memory channel and to perform error correction on errors associated with memory devices in the second group on the memory channel.
    Type: Grant
    Filed: December 11, 2013
    Date of Patent: June 16, 2015
    Assignee: International Business Machines Corporation
    Inventors: Eldee Stephens, Patrick J. Meaney, Judy S. Johnson, Luis A. Lastras-Montano
  • Patent number: 9058896
    Abstract: A refresh of a DRAM having at least a fast and a slow refresh rate includes encoding a pointer on a row or rows with refresh information, reading the refresh information, and incrementing a fast refresh address counter with the refresh information. The refresh may be performed by encoding one or more cells on a row that may require a fast refresh, one or more cells on a group of rows that may require a fast refresh, or one or more cells on a row that may not require a fast refresh.
    Type: Grant
    Filed: August 29, 2012
    Date of Patent: June 16, 2015
    Assignee: International Business Machines Corporation
    Inventors: Michele M. Franceschini, Hillery Hunter, Ashish Jagmohan, Charles A. Kilmer, Kyu-Hyoun Kim, Luis A. Lastras, Moinuddin K. Qureshi
  • Patent number: 9037930
    Abstract: This disclosure includes a method for preventing errors in a DRAM (dynamic random access memory) due to weak cells that includes determining the location of a weak cell in a DRAM row, receiving data to write to the DRAM, and encoding the data into a bit vector to be written to memory. For each weak cell location, the corresponding bit from the bit vector is equal to the reliable logic state of the weak cell and the bit vector is longer than the data.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: May 19, 2015
    Assignee: International Business Machines Corporation
    Inventors: Michele M. Franceschini, Hillery C. Hunter, Ashish Jagmohan, Charles A. Kilmer, Kyu-hyoun Kim, Luis A. Lastras-Montano, Moinuddin K. Qureshi
  • Publication number: 20150121167
    Abstract: A memory controller is equipped with multiple error correction circuits for different complexity levels of errors, but requested data is initially sent to a requesting unit (e.g., processor) via a bypass path which provides the lowest memory latency. The requesting unit performs error detection and, if an error is found, sends a retry select signal to the memory controller. The retry select signal provides an indication of which error correction unit should be used to provide complete correction of the error but add the minimum latency necessary. On the retry transmission, the controller uses the particular error correction unit indicated by the retry select signal. The memory controller can also have a persistent error detection circuit which identifies an address as being defective when an error is repeatedly indicated by multiple retry select signals, and the control logic can automatically transmits the requested data using the appropriate error correction unit.
    Type: Application
    Filed: December 6, 2013
    Publication date: April 30, 2015
    Applicant: International Business Machines Corporation
    Inventors: Benjiman L. Goodman, Luis A. Lastras-Montano, Eric E. Retter, Kenneth L. Wright
  • Publication number: 20150121166
    Abstract: A memory controller is equipped with multiple error correction circuits for different complexity levels of errors, but requested data is initially sent to a requesting unit (e.g., processor) via a bypass path which provides the lowest memory latency. The requesting unit performs error detection and, if an error is found, sends a retry select signal to the memory controller. The retry select signal provides an indication of which error correction unit should be used to provide complete correction of the error but add the minimum latency necessary. On the retry transmission, the controller uses the particular error correction unit indicated by the retry select signal. The memory controller can also have a persistent error detection circuit which identifies an address as being defective when an error is repeatedly indicated by multiple retry select signals, and the control logic can automatically transmits the requested data using the appropriate error correction unit.
    Type: Application
    Filed: October 24, 2013
    Publication date: April 30, 2015
    Applicant: International Business Machines Corporation
    Inventors: Benjiman L. Goodman, Luis A. Lastras-Montano, Eric E. Retter, Kenneth L. Wright
  • Patent number: 9001609
    Abstract: A method and apparatus for managing memory in an electronic system is described. The method includes determining a failure in an element of the memory array that is repairable by a redundant element. The method may further include using a latch to identify the redundant element. The method may also include that upon an event, using a value in the latch in an eFuse which subsequently selects the redundant element.
    Type: Grant
    Filed: January 2, 2013
    Date of Patent: April 7, 2015
    Assignee: International Business Machines Corporation
    Inventors: Michele M. Franceschini, Hillery C. Hunter, Charles A. Kilmer, Kyu-hyoun Kim, Luis A. Lastras-Montano
  • Patent number: 8995217
    Abstract: A method and apparatus for managing memory in an electronic system is described. The method includes determining a failure in an element of the memory array that is repairable by a redundant element. The method may further include using a latch to identify the redundant element. The method may also include that upon an event, using a value in the latch in an eFuse which subsequently selects the redundant element.
    Type: Grant
    Filed: March 4, 2013
    Date of Patent: March 31, 2015
    Assignee: International Business Machines Corporation
    Inventors: Michele M. Franceschini, Hillery C. Hunter, Charles A. Kilmer, Kyu-hyoun Kim, Luis A. Lastras-Montano
  • Publication number: 20150089279
    Abstract: A method, system and computer program product are provided for implementing ECC (Error Correction Codes) memory module communications with a host processor in multi-ported memory configurations in a computer system. Each of multiple memory modules operating in unison is enabled to identify which memory module is the one required to communicate module specific information back to the host processor. All of the multiple memory modules operating in unison are enabled to generate back to the host processor a valid ECC word, while other multiple memory modules individually being unaware of data contents of the one memory module required to communicate back to the processor.
    Type: Application
    Filed: September 24, 2013
    Publication date: March 26, 2015
    Applicant: International Business Machines Corporation
    Inventors: John S. Dodson, Luis A. Lastras-Montano, Warren E. Maule, Adam J. McPadden, Kenneth L. Wright
  • Patent number: 8990217
    Abstract: A method for receiving a data stream that includes data samples, each data sample having one of a plurality of actual values. For each data sample in the data stream, a first index in a dictionary is selected. The dictionary includes indices corresponding to each of the plurality of actual values. The first index corresponds to an actual value of the data sample. A predicted value of the data sample is generated in response to previously received data samples in the data stream and to a prediction algorithm. A second index in the dictionary that corresponds to an actual value in the dictionary that is closest to the value of the predicted value is selected. The difference between the first index and the second index is calculated and compressed. The compressed difference between the first index and the second index is then output. This process is performed for each data sample in the data stream.
    Type: Grant
    Filed: July 13, 2011
    Date of Patent: March 24, 2015
    Assignee: International Business Machines Corporation
    Inventors: Ashish Jagmohan, Joshua W. Knight, Luis A. Lastras-Montano
  • Publication number: 20150019905
    Abstract: Embodiments relate to stale data detection in a marked channel for a scrub. An aspect includes bringing the marked channel online, wherein the computer comprises a plurality of memory channels comprising the marked channel and a remaining plurality of unmarked channels. Another aspect includes performing a scrub read of an address in the plurality of memory channels. Another aspect includes determining whether data returned by the scrub read from the marked channel is valid or stale based on data returned from the unmarked channels by the scrub read. Another aspect includes based on determining that the data returned by the scrub read from the marked channel is valid, not performing a scrub writeback to the marked channel. Another aspect includes based on determining that the data returned by the scrub read from the marked channel is stale, performing a scrub writeback of corrected data to the marked channel.
    Type: Application
    Filed: September 30, 2014
    Publication date: January 15, 2015
    Inventors: Luis A. Lastras, Patrick J. Meaney, Eldee Stephens, George C. Wellwood
  • Publication number: 20140365584
    Abstract: Embodiments relate to personalized low latency communications. A method may include receiving a description of content of a message, receiving recipient data corresponding to at least two possible recipients within a population of possible recipients, and selecting a relevant subpopulation of the population. The selecting may include, for each of the at least two possible recipients, ranking a strength of an indirect relationship between the description and the recipient data. The indirect relationship may be based on the description, the recipient data and at least one additional data source. The selecting may also include, for each of the at least two possible recipients, adding a possible recipient to the relevant subpopulation based on the ranking of the indirect relationship associated with the possible recipient. The method may further include initiating a two-way communication channel between a sender of the message and the relevant subpopulation.
    Type: Application
    Filed: July 16, 2013
    Publication date: December 11, 2014
    Inventors: Bulent Abali, Michele M. Franceschini, Ashish Jagmohan, Luis A. Lastras-Montano, Livio Soares
  • Publication number: 20140365504
    Abstract: Embodiments relate to estimating closeness of topics based on graph analytics. A graph that includes a plurality of nodes and edges is accessed. Each node in the graph represents a topic and each edge represents a known association between two topics. A statistical traversal experiment is performed on the graph. A strength of relations between any two topics represented by nodes in the graph is inferred based on statistics extracted from the statistical traversal experiment.
    Type: Application
    Filed: July 16, 2013
    Publication date: December 11, 2014
    Inventors: Michele M. Franceschini, Ashish Jagmohan, Luis A. Lastras-Montano, Livio Soares
  • Publication number: 20140365503
    Abstract: Embodiments relate to estimating closeness of topics based on graph analytics. A graph that includes a plurality of nodes and edges is accessed. Each node in the graph represents a topic and each edge represents a known association between two topics. A statistical traversal experiment is performed on the graph. A strength of relations between any two topics represented by nodes in the graph is inferred based on statistics extracted from the statistical traversal experiment.
    Type: Application
    Filed: June 11, 2013
    Publication date: December 11, 2014
    Inventors: Michele M. Franceschini, Ashish Jagmohan, Luis A. Lastras Montano, Livio Soares
  • Publication number: 20140365480
    Abstract: Embodiments relate to personalized low latency communications. A method may include receiving a description of content of a message, receiving recipient data corresponding to at least two possible recipients within a population of possible recipients, and selecting a relevant subpopulation of the population. The selecting may include, for each of the at least two possible recipients, ranking a strength of an indirect relationship between the description and the recipient data. The indirect relationship may be based on the description, the recipient data and at least one additional data source. The selecting may also include, for each of the at least two possible recipients, adding a possible recipient to the relevant subpopulation based on the ranking of the indirect relationship associated with the possible recipient. The method may further include initiating a two-way communication channel between a sender of the message and the relevant subpopulation.
    Type: Application
    Filed: June 11, 2013
    Publication date: December 11, 2014
    Inventors: Bulent Abali, Michele M. Franceschini, Ashish Jagmohan, Luis A. Lastras-Montano, Livio Soares
  • Patent number: 8897062
    Abstract: Systems, methods, and devices for iteratively writing contents to memory locations are provided. A statistical model is used to determine a sequence of pulses to write desired contents to a memory location. The contents can be expressed as a resistance value in a range to store one or more bits in a memory cell. For phase change memory, an adaptive reset pulse and one or more annealing pulses are selected based on a desired resistance range. Reading the resistance value of the memory cell can provide feedback to determine adjustments in an overall pulse application strategy. The statistical model and a look up table can be used to select and modify pulses. Adaptively updating the statistical model and look up table may reduce the number of looping iterations to shift the resistance value of the memory cell into the desired resistance range.
    Type: Grant
    Filed: June 1, 2011
    Date of Patent: November 25, 2014
    Assignee: International Business Machines Corporation
    Inventors: Matthew J. Breitwisch, Roger W. Cheek, Stefanie R. Chiras, Ibrahim M. Elfadel, Michele M. Franceschini, John P. Karidis, Luis A. Lastras-Montano, Thomas Mittelholzer, Mayank Sharma
  • Patent number: 8898544
    Abstract: This disclosure includes a method for correcting errors on a DRAM having an ECC which includes writing data to a DRAM row, reading data from the DRAM row, detecting errors in the data that cannot be corrected by the DRAM's ECC, determining erasure information for the row, evaluating the errors using the erasure information, and correcting the errors in the data.
    Type: Grant
    Filed: December 11, 2012
    Date of Patent: November 25, 2014
    Assignee: International Business Machines Corporation
    Inventors: Michele M. Franceschini, Hillery C. Hunter, Ashish Jagmohan, Charles A. Kilmer, Kyu-hyoun Kim, Luis A. Lastras-Montano, Moinuddin K. Qureshi