Patents by Inventor Vijayalakshmi Srinivasan

Vijayalakshmi Srinivasan 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: 9418721
    Abstract: Systems and methods to manage memory on a spin transfer torque magnetoresistive random-access memory (STT-MRAM) are provided. A particular method may include determining a performance characteristic using relationship information that relates a bit error rate to at least one of a programming pulse width, a temperature, a history-based predictive performance parameter, a coding scheme, and a voltage level also associated with a memory. The performance characteristic is stored and used to manage a write operation associated with the memory.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: August 16, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Patent number: 9411730
    Abstract: A mechanism is provided for memory coherence in a multiple processor system. Responsive to a memory operation from a processing core of the multiple processor system resulting in a cache miss, the mechanism checks a private region table associated with the processing core. The memory operation attempts to access a memory region. Responsive to determining the memory region corresponds to an entry in the private region table, the mechanism performs a remote memory controller snoop of a remote memory controller without snooping the multiple processor system.
    Type: Grant
    Filed: June 22, 2015
    Date of Patent: August 9, 2016
    Assignee: International Business Machines Corporation
    Inventors: David M. Daly, Vijayalakshmi Srinivasan
  • Patent number: 9406368
    Abstract: Systems and methods to manage memory on a spin transfer torque magnetoresistive random-access memory (STT-MRAM) are provided. A particular method of managing memory includes determining a temperature associated with the memory and determining a level of write queue utilization associated with the memory. A write operation may be performed based on the level of write queue utilization and the temperature.
    Type: Grant
    Filed: January 21, 2014
    Date of Patent: August 2, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Patent number: 9351899
    Abstract: Systems and methods to manage memory on a spin transfer torque magnetoresistive random-access memory (STT-MRAM) are provided. A particular method of managing memory includes determining a temperature associated with the memory and determining a level of write queue utilization associated with the memory. A write operation may be performed based on the level of write queue utilization and the temperature.
    Type: Grant
    Filed: June 30, 2014
    Date of Patent: May 31, 2016
    Assignee: International Business Machines Corporation
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Patent number: 9323676
    Abstract: Embodiments relate to a non-data inclusive coherent (NIC) directory for a symmetric multiprocessor (SMP) of a computer. An aspect includes determining a first eviction entry of a highest-level cache in a multilevel caching structure of the first processor node of the SMP. Another aspect includes determining that the NIC directory is not full. Another aspect includes determining that the first eviction entry of the highest-level cache is owned by a lower-level cache in the multilevel caching structure. Another aspect includes, based on the NIC directory not being full and based on the first eviction entry of the highest-level cache being owned by the lower-level cache, installing an address of the first eviction entry of the highest-level cache in a first new entry in the NIC directory. Another aspect includes invalidating the first eviction entry in the highest-level cache.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: April 26, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Timothy C. Bronson, Garrett M. Drapala, Rebecca M. Gott, Pak-Kin Mak, Vijayalakshmi Srinivasan, Craig R. Walters
  • Patent number: 9298466
    Abstract: A computer-implemented method for instruction execution in a pipeline, includes fetching, in the pipeline, a plurality of instructions, wherein the plurality of instructions includes a plurality of branch instructions, for each of the plurality of branch instructions, assigning a branch uncertainty to each of the plurality of branch instructions, for each of the plurality of instructions, assigning an instruction uncertainty that is a summation of branch uncertainties of older unresolved branches, and balancing the instructions, based on a current summation of instruction uncertainty, in the pipeline.
    Type: Grant
    Filed: October 15, 2012
    Date of Patent: March 29, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Alper Buyuktosunoglu, Brian R. Prasky, Vijayalakshmi Srinivasan
  • Patent number: 9292445
    Abstract: Embodiments relate to a non-data inclusive coherent (NIC) directory for a symmetric multiprocessor (SMP) of a computer. An aspect includes determining a first eviction entry of a highest-level cache in a multilevel caching structure of the first processor node of the SMP. Another aspect includes determining that the NIC directory is not full. Another aspect includes determining that the first eviction entry of the highest-level cache is owned by a lower-level cache in the multilevel caching structure. Another aspect includes, based on the NIC directory not being full and based on the first eviction entry of the highest-level cache being owned by the lower-level cache, installing an address of the first eviction entry of the highest-level cache in a first new entry in the NIC directory. Another aspect includes invalidating the first eviction entry in the highest-level cache.
    Type: Grant
    Filed: September 30, 2014
    Date of Patent: March 22, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Timothy C. Bronson, Garrett M. Drapala, Rebecca M. Gott, Pak-kin Mak, Vijayalakshmi Srinivasan, Craig R. Walters
  • Publication number: 20160062899
    Abstract: Embodiments relate to thread-based cache content savings for task switching in a computer processor. An aspect includes determining a cache entry in a cache of the computer processor that is owned by the first thread, wherein the determination is made based on a hardware thread identifier (ID) of the first thread matching a hardware thread ID in the cache entry. Another aspect includes determining whether the determined cache entry is eligible for prefetching. Yet another aspect includes, based on determining that the determined cache entry is eligible for prefetching, setting a marker in the cache entry to active.
    Type: Application
    Filed: August 26, 2014
    Publication date: March 3, 2016
    Inventors: Harold W. Cain, III, David M. Daly, Brian R. Prasky, Vijayalakshmi Srinivasan
  • Publication number: 20160062791
    Abstract: Embodiments relate to thread-based cache content savings for task switching in a computer processor. An aspect includes determining a cache entry in a cache of the computer processor that is owned by the first thread, wherein the determination is made based on a hardware thread identifier (ID) of the first thread matching a hardware thread ID in the cache entry. Another aspect includes determining whether the determined cache entry is eligible for prefetching. Yet another aspect includes, based on determining that the determined cache entry is eligible for prefetching, setting a marker in the cache entry to active.
    Type: Application
    Filed: October 30, 2014
    Publication date: March 3, 2016
    Inventors: Harold W. Cain, III, David M. Daly, Brian R. Prasky, Vijayalakshmi Srinivasan
  • Publication number: 20150331802
    Abstract: A scheme referred to as a “Region-based cache restoration prefetcher” (RECAP) is employed for cache preloading on a partition or a context switch. The RECAP exploits spatial locality to provide a bandwidth-efficient prefetcher to reduce the “cold” cache effect caused by multiprogrammed virtualization. The RECAP groups cache blocks into coarse-grain regions of memory, and predicts which regions contain useful blocks that should be prefetched the next time the current virtual machine executes. Based on these predictions, and using a simple compression technique that also exploits spatial locality, the RECAP provides a robust prefetcher that improves performance without excessive bandwidth overhead or slowdown.
    Type: Application
    Filed: July 27, 2015
    Publication date: November 19, 2015
    Inventors: Harold W. Cain, III, Vijayalakshmi Srinivasan, Jason Zebchuk
  • Patent number: 9182991
    Abstract: A computer system for instruction execution includes a processor having a pipeline. The system is configured to perform a method including fetching, in the pipeline, a plurality of instructions, wherein the plurality of instructions includes a plurality of branch instructions, for each of the plurality of branch instructions, assigning a branch uncertainty to each of the plurality of branch instructions, for each of the plurality of instructions, assigning an instruction uncertainty that is a summation of branch uncertainties of older unresolved branches and balancing the instructions, based on a current summation of instruction uncertainty, in the pipeline.
    Type: Grant
    Filed: February 6, 2012
    Date of Patent: November 10, 2015
    Assignee: International Business Machines Corporation
    Inventors: Alper Buyuktosunoglu, Brian R. Prasky, Vijayalakshmi Srinivasan
  • Patent number: 9092341
    Abstract: A scheme referred to as a “Region-based cache restoration prefetcher” (RECAP) is employed for cache preloading on a partition or a context switch. The RECAP exploits spatial locality to provide a bandwidth-efficient prefetcher to reduce the “cold” cache effect caused by multiprogrammed virtualization. The RECAP groups cache blocks into coarse-grain regions of memory, and predicts which regions contain useful blocks that should be prefetched the next time the current virtual machine executes. Based on these predictions, and using a simple compression technique that also exploits spatial locality, the RECAP provides a robust prefetcher that improves performance without excessive bandwidth overhead or slowdown.
    Type: Grant
    Filed: July 10, 2012
    Date of Patent: July 28, 2015
    Assignee: International Business Machines Corporation
    Inventors: Harold W. Cain, III, Vijayalakshmi Srinivasan, Jason Zebchuk
  • Publication number: 20150206567
    Abstract: Systems and methods to manage memory on a spin transfer torque magnetoresistive random-access memory (STT-MRAM) are provided. A particular method of managing memory includes determining a temperature associated with the memory and determining a level of write queue utilization associated with the memory. A write operation may be performed based on the level of write queue utilization and the temperature.
    Type: Application
    Filed: January 21, 2014
    Publication date: July 23, 2015
    Applicant: International Business Machines Corporation
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Publication number: 20150206566
    Abstract: Systems and methods to manage memory on a spin transfer torque magnetoresistive random-access memory (STT-MRAM) are provided. A particular method may include determining a performance characteristic using relationship information that relates a bit error rate to at least one of a programming pulse width, a temperature, a history-based predictive performance parameter , a coding scheme, and a voltage level also associated with a memory. The performance characteristic is stored and used to manage a write operation associated with the memory.
    Type: Application
    Filed: January 21, 2014
    Publication date: July 23, 2015
    Applicant: International Business Machines Corporation
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Publication number: 20150206568
    Abstract: Systems and methods to manage memory on a spin transfer torque magnetoresistive random-access memory (STT-MRAM) are provided. A particular method may include determining a performance characteristic using relationship information that relates a bit error rate to at least one of a programming pulse width, a temperature, a history-based predictive performance parameter , a coding scheme, and a voltage level also associated with a memory. The performance characteristic is stored and used to manage a write operation associated with the memory.
    Type: Application
    Filed: June 30, 2014
    Publication date: July 23, 2015
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Publication number: 20150206569
    Abstract: Systems and methods to manage memory on a spin transfer torque magnetoresistive random-access memory (STT-MRAM) are provided. A particular method of managing memory includes determining a temperature associated with the memory and determining a level of write queue utilization associated with the memory. A write operation may be performed based on the level of write queue utilization and the temperature.
    Type: Application
    Filed: June 30, 2014
    Publication date: July 23, 2015
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Patent number: 9069545
    Abstract: Systems and methods are disclosed that allow atomic updates to global data to be at least partially eliminated to reduce synchronization overhead in parallel computing. A compiler analyzes the data to be processed to selectively permit unsynchronized data transfer for at least one type of data. A programmer may provide a hint to expressly identify the type of data that are candidates for unsynchronized data transfer. In one embodiment, the synchronization overhead is reducible by generating an application program that selectively substitutes codes for unsynchronized data transfer for a subset of codes for synchronized data transfer. In another embodiment, the synchronization overhead is reducible by employing a combination of software and hardware by using relaxation data registers and decoders that collectively convert a subset of commands for synchronized data transfer into commands for unsynchronized data transfer.
    Type: Grant
    Filed: July 18, 2011
    Date of Patent: June 30, 2015
    Assignee: International Business Machines Corporation
    Inventors: Lakshminarayanan Renganarayana, Vijayalakshmi Srinivasan
  • Publication number: 20150074356
    Abstract: A processor and a method implemented by the processor to obtain computation results are described. The processor includes a unified reuse table embedded in a processor pipeline, the unified reuse table including a plurality of entries, each entry of the plurality of entries corresponding with a computation instruction or a set of computation instructions. The processor also includes a functional unit to perform a computation based on a corresponding instruction.
    Type: Application
    Filed: October 15, 2013
    Publication date: March 12, 2015
    Applicant: International Business Machines Corporation
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Publication number: 20150074381
    Abstract: A processor and a method implemented by the processor to obtain computation results are described. The processor includes a unified reuse table embedded in a processor pipeline, the unified reuse table including a plurality of entries, each entry of the plurality of entries corresponding with a computation instruction or a set of computation instructions. The processor also includes a functional unit to perform a computation based on a corresponding instruction.
    Type: Application
    Filed: September 6, 2013
    Publication date: March 12, 2015
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Pradip Bose, Alper Buyuktosunoglu, Xiaochen Guo, Hillery C. Hunter, Jude A. Rivers, Vijayalakshmi Srinivasan
  • Publication number: 20150058569
    Abstract: Embodiments relate to a non-data inclusive coherent (NIC) directory for a symmetric multiprocessor (SMP) of a computer. An aspect includes determining a first eviction entry of a highest-level cache in a multilevel caching structure of the first processor node of the SMP. Another aspect includes determining that the NIC directory is not full. Another aspect includes determining that the first eviction entry of the highest-level cache is owned by a lower-level cache in the multilevel caching structure. Another aspect includes, based on the NIC directory not being full and based on the first eviction entry of the highest-level cache being owned by the lower-level cache, installing an address of the first eviction entry of the highest-level cache in a first new entry in the NIC directory. Another aspect includes invalidating the first eviction entry in the highest-level cache.
    Type: Application
    Filed: September 30, 2014
    Publication date: February 26, 2015
    Inventors: Timothy C. Bronson, Garrett M. Drapala, Rebecca M. Gott, Pak-kin Mak, Vijayalakshmi Srinivasan, Craig R. Walters