Patents by Inventor Sandhya Dwarkadas

Sandhya Dwarkadas 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: 9411733
    Abstract: A method and directory system that recognizes and represents the subset of sharing patterns present in an application is provided. As used herein, the term sharing pattern refers to a group of processors accessing a single memory location in an application. The sharing pattern is decoupled from each cache line and held in a separate directory table. The sharing pattern of a cache block is the bit vector representing the processors that share the block. Multiple cache lines that have the same sharing pattern point to a common entry in the directory table. In addition, when the table capacity is exceeded, patterns that are similar to each other are dynamically collated into a single entry.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: August 9, 2016
    Assignee: University of Rochester
    Inventors: Hongzhou Zhao, Arrvindh Shriraman, Sandhya Dwarkadas
  • Patent number: 8661204
    Abstract: The present invention employs three decoupled hardware mechanisms: read and write signatures, which summarize per-thread access sets; per-thread conflict summary tables, which identify the threads with which conflicts have occurred; and a lazy versioning mechanism, which maintains the speculative updates in the local cache and employs a thread-private buffer (in virtual memory) only in the rare event of an overflow. The conflict summary tables allow lazy conflict management to occur locally, with no global arbitration (they also support eager management). All three mechanisms are kept software-accessible, to enable virtualization and to support transactions of arbitrary length.
    Type: Grant
    Filed: March 16, 2012
    Date of Patent: February 25, 2014
    Assignee: University of Rochester, Office of Technology Transfer
    Inventors: Sandhya Dwarkadas, Arrvindh Shriraman, Michael Scott
  • Publication number: 20140032848
    Abstract: A method and directory system that recognizes and represents the subset of sharing patterns present in an application is provided. As used herein, the term sharing pattern refers to a group of processors accessing a single memory location in an application. The sharing pattern is decoupled from each cache line and held in a separate directory table. The sharing pattern of a cache block is the bit vector representing the processors that share the block. Multiple cache lines that have the same sharing pattern point to a common entry in the directory table. In addition, when the table capacity is exceeded, patterns that are similar to each other are dynamically collated into a single entry.
    Type: Application
    Filed: September 7, 2012
    Publication date: January 30, 2014
    Applicant: UNIVERSITY OF ROCHESTER
    Inventors: Hongzhou ZHAO, Arrvindh SHRIRAMAN, Sandhya DWARKADAS
  • Publication number: 20120179877
    Abstract: The present invention employs three decoupled hardware mechanisms: read and write signatures, which summarize per-thread access sets; per-thread conflict summary tables, which identify the threads with which conflicts have occurred; and a lazy versioning mechanism, which maintains the speculative updates in the local cache and employs a thread-private buffer (in virtual memory) only in the rare event of an overflow. The conflict summary tables allow lazy conflict management to occur locally, with no global arbitration (they also support eager management). All three mechanisms are kept software-accessible, to enable virtualization and to support transactions of arbitrary length.
    Type: Application
    Filed: March 16, 2012
    Publication date: July 12, 2012
    Applicant: University of Rochester, Office of Technology Transfer
    Inventors: Arrvindh SHRIRAMAN, Sandhya DWARKADAS, Michael SCOTT
  • Patent number: 8180971
    Abstract: In a transactional memory technique, hardware serves simply to optimize the performance of transactions that are controlled fundamentally by software. The hardware support reduces the overhead of common TM tasks—conflict detection, validation, and data isolation—for common-case bounded transactions. Software control preserves policy flexibility and supports transactions unbounded in space and in time. The hardware includes 1) an alert-on-update mechanism for fast software-controlled conflict detection; and 2) programmable data isolation, allowing potentially conflicting readers and writers to proceed concurrently under software control.
    Type: Grant
    Filed: October 26, 2010
    Date of Patent: May 15, 2012
    Assignee: University of Rochester
    Inventors: Michael Scott, Sandhya Dwarkadas, Arrvindh Shriraman, Virendra Marathe, Michael F. Spear
  • Patent number: 8103856
    Abstract: In a processor having multiple clusters which operate in parallel, the number of clusters in use can be varied dynamically. At the start of each program phase, the configuration option for an interval is run to determine the optimal configuration, which is used until the next phase change is detected. The optimum instruction interval is determined by starting with a minimum interval and doubling it until a low stability factor is reached.
    Type: Grant
    Filed: January 12, 2009
    Date of Patent: January 24, 2012
    Assignee: University of Rochester
    Inventors: Rajeev Balasubramonian, Sandhya Dwarkadas, David Albonesi
  • Publication number: 20110099335
    Abstract: In a transactional memory technique, hardware serves simply to optimize the performance of transactions that are controlled fundamentally by software. The hardware support reduces the overhead of common TM tasks—conflict detection, validation, and data isolation—for common-case bounded transactions. Software control preserves policy flexibility and supports transactions unbounded in space and in time. The hardware includes 1) an alert-on-update mechanism for fast software-controlled conflict detection; and 2) programmable data isolation, allowing potentially conflicting readers and writers to proceed concurrently under software control.
    Type: Application
    Filed: October 26, 2010
    Publication date: April 28, 2011
    Applicant: University of Rochester
    Inventors: Michael L. Scott, Sandhya Dwarkadas, Arrvindh Shriraman, Virendra Marathe, Michael F. Spear
  • Patent number: 7739537
    Abstract: A multiple clock domain (MCD) microarchitecture uses a globally-asynchronous, locally-synchronous (GALS) clocking style. In an MCD microprocessor each functional block operates with a separately generated clock, and synchronizing circuits ensure reliable inter-domain communication. Thus, fully synchronous design practices are used in the design of each domain.
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: June 15, 2010
    Inventors: David Albonesi, Greg Semeraro, Grigorios Magklis, Michael L. Scott, Rajeev Balasubramonian, Sandhya Dwarkadas
  • Publication number: 20090216997
    Abstract: In a processor having multiple clusters which operate in parallel, the number of clusters in use can be varied dynamically. At the start of each program phase, the configuration option for an interval is run to determine the optimal configuration, which is used until the next phase change is detected. The optimum instruction interval is determined by starting with a minimum interval and doubling it until a low stability factor is reached.
    Type: Application
    Filed: January 12, 2009
    Publication date: August 27, 2009
    Inventors: Rajeev Balasubramonian, Sandhya Dwarkadas, David Albonesi
  • Patent number: 7490220
    Abstract: In a processor having multiple clusters which operate in parallel, the number of clusters in use can be varied dynamically. At the start of each program phase, the configuration option for an interval is run to determine the optimal configuration, which is used until the next phase change is detected. The optimum instruction interval is determined by starting with a minimum interval and doubling it until a low stability factor is reached.
    Type: Grant
    Filed: June 8, 2005
    Date of Patent: February 10, 2009
    Inventors: Rajeev Balasubramonian, Sandhya Dwarkadas, David Albonesi
  • Publication number: 20080059968
    Abstract: Disclosed are a method and system for predicting future values of a target metric associated with a task executed on a computer system. The method comprises the steps of, over a given period of time, measuring at least one defined metric, transforming that measurement into a value for a predictor source metric, and using the value for the predictor source metric to obtain a predicted future value for said target metric. The preferred embodiment of this invention provides a flexible performance multi-predictor to solve the problem of providing accurate future behavior predictions for adaptive reconfiguration systems. The multi-predictor makes predictions about future workload characteristic by periodically reading available hardware counters. Also disclosed is a method and system for periodically reconfiguring an adaptive computer system by rescheduling tasks based on future behavior predictions.
    Type: Application
    Filed: October 29, 2007
    Publication date: March 6, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Gheorghe Cascaval, Evelyn Duesterwald, Sandhya Dwarkadas
  • Patent number: 7289939
    Abstract: Disclosed are a method and system for predicting future values of a target metric associated with a task executed on a computer system. The method comprises the steps of, over a given period of time, measuring at least one defined metric, transforming that measurement into a value for a predictor source metric, and using the value for the predictor source metric to obtain a predicted future value for said target metric. The preferred embodiment of this invention provides a flexible performance multi-predictor to solve the problem of providing accurate future behavior predictions for adaptive reconfiguration systems. The multi-predictor makes predictions about future workload characteristic by periodically reading available hardware counters. Also disclosed is a method and system for periodically reconfiguring an adaptive computer system by rescheduling tasks based on future behavior predictions.
    Type: Grant
    Filed: May 4, 2006
    Date of Patent: October 30, 2007
    Assignee: International Business Machines Corporation
    Inventors: Gheorghe C. Cascaval, Evelyn Duesterwald, Sandhya Dwarkadas
  • Publication number: 20070016817
    Abstract: A multiple clock domain (MCD) microarchitecture uses a globally-asynchronous, locally-synchronous (GALS) clocking style. In an MCD microprocessor each functional block operates with a separately generated clock, and synchronizing circuits ensure reliable inter-domain communication. Thus, fully synchronous design practices are used in the design of each domain.
    Type: Application
    Filed: March 27, 2006
    Publication date: January 18, 2007
    Inventors: David Albonesi, Greg Semeraro, Grigorios Magklis, Michael Scott, Rajeev Balasubramonian, Sandhya Dwarkadas
  • Publication number: 20060217940
    Abstract: Disclosed are a method and system for predicting future values of a target metric associated with a task executed on a computer system. The method comprises the steps of, over a given period of time, measuring at least one defined metric, transforming that measurement into a value for a predictor source metric, and using the value for the predictor source metric to obtain a predicted future value for said target metric. The preferred embodiment of this invention provides a flexible performance multi-predictor to solve the problem of providing accurate future behavior predictions for adaptive reconfiguration systems. The multi-predictor makes predictions about future workload characteristic by periodically reading available hardware counters. Also disclosed is a method and system for periodically reconfiguring an adaptive computer system by rescheduling tasks based on future behavior predictions.
    Type: Application
    Filed: May 4, 2006
    Publication date: September 28, 2006
    Applicant: International Business Machines Corporation
    Inventors: Gheorghe Cascaval, Evelyn Duesterwald, Sandhya Dwarkadas
  • Patent number: 7089443
    Abstract: A multiple clock domain (MCD) microarchitecture uses a globally-asynchronous, locally-synchronous (GALS) clocking style. In an MCD microprocessor each functional block operates with a separately generated clock, and synchronizing circuits ensure reliable inter-domain communication. Thus, fully synchronous design practices are used in the design of each domain.
    Type: Grant
    Filed: January 23, 2004
    Date of Patent: August 8, 2006
    Assignee: University of Rochester
    Inventors: David Albonesi, Greg Semeraro, Grigorios Magklis, Michael L. Scott, Rajeev Balasubramonian, Sandhya Dwarkadas
  • Patent number: 7072805
    Abstract: Disclosed are a method and system for predicting future values of a target metric associated with a task executed on a computer system. The method includes the steps of, over a given period of time, measuring at least one defined metric, transforming that measurement into a value for a predictor source metric, and using the value for the predictor source metric to obtain a predicted future value for said target metric. The preferred embodiment of this invention provides a flexible performance multi-predictor to solve the problem of providing accurate future behavior predictions for adaptive reconfiguration systems. The multi-predictor makes predictions about future workload characteristic by periodically reading available hardware counters. Also disclosed is a method and system for periodically reconfiguring an adaptive computer system by rescheduling tasks based on future behavior predictions.
    Type: Grant
    Filed: October 17, 2003
    Date of Patent: July 4, 2006
    Assignee: International Business Machines Corporation
    Inventors: Gheorghe C. Cascaval, Evelyn Duesterwald, Sandhya Dwarkadas
  • Publication number: 20060106923
    Abstract: In a processor having multiple clusters which operate in parallel, the number of clusters in use can be varied dynamically. At the start of each program phase, the configuration option for an interval is run to determine the optimal configuration, which is used until the next phase change is detected. The optimum instruction interval is determined by starting with a minimum interval and doubling it until a low stability factor is reached.
    Type: Application
    Filed: June 8, 2005
    Publication date: May 18, 2006
    Inventors: Rajeev Balasubramonian, Sandhya Dwarkadas, David Albonesi
  • Publication number: 20050086029
    Abstract: Disclosed are a method and system for predicting future values of a target metric associated with a task executed on a computer system. The method comprises the steps of, over a given period of time, measuring at least one defined metric, transforming that measurement into a value for a predictor source metric, and using the value for the predictor source metric to obtain a predicted future value for said target metric. The preferred embodiment of this invention provides a flexible performance multi-predictor to solve the problem of providing accurate future behavior predictions for adaptive reconfiguration systems. The multi-predictor makes predictions about future workload characteristic by periodically reading available hardware counters. Also disclosed is a method and system for periodically reconfiguring an adaptive computer system by rescheduling tasks based on future behavior predictions.
    Type: Application
    Filed: October 17, 2003
    Publication date: April 21, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Gheorghe Cascaval, Evelyn Duesterwald, Sandhya Dwarkadas
  • Patent number: RE41958
    Abstract: A cache and TLB layout and design leverage repeater insertion to provide dynamic low-cost configurability trading off size and speed on a per application phase basis. A configuration management algorithm dynamically detects phase changes and reacts to an application's hit and miss intolerance in order to improve memory hierarchy performance while taking energy consumption into consideration.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: November 23, 2010
    Inventors: Sandhya Dwarkadas, Rajeev Balasubramonian, Alper Buyuktosunoglu, David H. Albonesi
  • Patent number: RE42213
    Abstract: A cache and TLB layout and design leverage repeater insertion to provide dynamic low-cost configurability trading off size and speed on a per application phase basis. A configuration management algorithm dynamically detects phase changes and reacts to an application's hit and miss intolerance in order to improve memory hierarchy performance while taking energy consumption into consideration.
    Type: Grant
    Filed: January 24, 2006
    Date of Patent: March 8, 2011
    Assignee: University of Rochester
    Inventors: Sandhya Dwarkadas, Rajeev Balasubramonian, Alper Buyuktosunoglu, David H. Albonesi