Patents by Inventor Anil Krishna

Anil Krishna 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: 7610449
    Abstract: A single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines. Power is conserved by guiding access to lines stored in the cache and lowering cache clock speed relative to the central processor clock speed.
    Type: Grant
    Filed: October 4, 2006
    Date of Patent: October 27, 2009
    Assignee: International Business Machines Corporation
    Inventors: Gordon T. Davis, Richard W. Doing, John D. Jabusch, M V V Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20090157968
    Abstract: A cache memory including a plurality of sets of cache lines, and providing an implementation for increasing the associativity of selected sets of cache lines including the combination of providing a group of parameters for determining the worthiness of a cache line stored in a basic set of cache lines, providing a partner set of cache lines, in the cache memory, associated with the basic set, applying the group of parameters to determine the worthiness level of a cache line in the basic set and responsive to a determination of a worthiness in excess of a predetermined level, for a cache line, storing said worthiness level cache line in said partner set.
    Type: Application
    Filed: December 12, 2007
    Publication date: June 18, 2009
    Applicant: International Business Machines Corporation
    Inventors: Gordon B. Bell, Anil Krishna, Nicholas D. Lindbert, Ken V. Vu
  • Publication number: 20080282028
    Abstract: Embodiments of the present invention address deficiencies of the art in respect to memory management and provide a method, system and computer program product for dynamic optimization of DRAM controller page policy. In one embodiment of the invention, a memory module can include multiple different memories, each including a memory controller coupled to a memory array of memory pages. Each of the memory pages in turn can include a corresponding locality tendency state. A memory bank can be coupled to a sense amplifier and configured to latch selected ones of the memory pages responsive to the memory controller. Finally, the module can include open page policy management logic coupled to the memory controller. The logic can include program code enabled to granularly change open page policy management of the memory bank responsive to identifying a locality tendency state for a page loaded in the memory bank.
    Type: Application
    Filed: May 9, 2007
    Publication date: November 13, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ganesh Balakrishnan, Anil Krishna
  • Publication number: 20080282029
    Abstract: A design structure embodied in a machine readable storage medium for designing, manufacturing, and/or testing a design for dynamic optimization of DRAM controller page policy is provided. The design structure can include a memory module, which can include multiple different memories, each including a memory controller coupled to a memory array of memory pages. Each of the memory pages in turn can include a corresponding locality tendency state. A memory bank can be coupled to a sense amplifier and configured to latch selected ones of the memory pages responsive to the memory controller. Finally, the module can include open page policy management logic coupled to the memory controller. The logic can include program code enabled to granularly change open page policy management of the memory bank responsive to identifying a locality tendency state for a page loaded in the memory bank.
    Type: Application
    Filed: April 25, 2008
    Publication date: November 13, 2008
    Inventors: Ganesh Balakrishnan, Anil Krishna
  • Publication number: 20080250206
    Abstract: A design structure embodied in a machine readable storage medium for designing, manufacturing, and/or testing a design for a single unified level one instruction(s) cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instruction(s) consistent with conventional cache lines is provided. Formation of trace lines in the cache is delayed on initial operation of the system to assure quality of the trace lines stored.
    Type: Application
    Filed: May 7, 2008
    Publication date: October 9, 2008
    Inventors: Gordon T. Davis, Richard W. Doing, John D. Jabusch, M.V.V. Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20080250207
    Abstract: A single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines. Control is exercised over which lines are contained within the cache. This invention avoids inefficiencies in the cache by removing trace lines experiencing early exits from the cache, or trace lines that are short, by maintaining a few bits of information about the accuracy of the control flow in a trace cache line and using that information in addition to the LRU (Least Recently Used) bits that maintain the recency information of a cache line, in order to make a replacement decision.
    Type: Application
    Filed: May 12, 2008
    Publication date: October 9, 2008
    Inventors: GORDON T. DAVIS, Richard W. Doing, John D. Jabusch, M.V.V. Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20080235500
    Abstract: A design structure embodied in a machine readable storage medium for at least one of designing, manufacturing, and testing a design for a single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines is provided. Instruction branches are predicted taken or not taken using a highly accurate branch history table (BHT). Branches that are predicted not taken are appended to a trace buffer and the next basic block is constructed from the remaining instructions in the fetch buffer. Branches that are predicted taken flush the remaining fetch buffer and the next address is determined using a Branch Target Address Register (BTAC).
    Type: Application
    Filed: June 2, 2008
    Publication date: September 25, 2008
    Inventors: GORDON T. DAVIS, Richard W. Doing, John D. Jabusch, M. V.V. Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20080120468
    Abstract: A single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines. Instruction branches are predicted taken or not taken using a highly accurate branch history table (BHT). Branches that are predicted not taken are appended to a trace buffer and the next basic block is constructed from the remaining instructions in the fetch buffer. Branches that are predicted taken flush the remaining fetch buffer and the next address is determined using a Branch Target Address Register (BTAC).
    Type: Application
    Filed: November 21, 2006
    Publication date: May 22, 2008
    Inventors: Gordon T. Davis, Richard W. Doing, John D. Jabusch, M V V Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20080114964
    Abstract: A single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines. Control is exercised over which lines are contained within the cache. This invention avoids inefficiencies in the cache by removing trace lines experiencing early exits from the cache, or trace lines that are short, by maintaining a few bits of information about the accuracy of the control flow in a trace cache line and using that information in addition to the LRU (Least Recently Used) bits that maintain the recency information of a cache line, in order to make a replacement decision.
    Type: Application
    Filed: November 14, 2006
    Publication date: May 15, 2008
    Inventors: Gordon T. Davis, Richard W. Doing, John D. Jabusch, M V V Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20080098176
    Abstract: A method and apparatus implement memory accesses to a memory using an open page mode with data prefetching. A central processor unit issues memory commands. A memory controller receiving the memory commands, identifies a data prefetching command. The memory controller checks whether a next sequential line for the identified prefetch command is within the page currently being accessed, and responsive to identifying the next sequential line being within the current page, the current command is processed and the current page left open.
    Type: Application
    Filed: October 18, 2006
    Publication date: April 24, 2008
    Inventors: M. V. V. Anil Krishna, Michael Raymond Trombley, Steven Paul VanderWeil
  • Publication number: 20080086597
    Abstract: A single unified level one instruction(s) cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instruction(s) consistent with conventional cache lines. Formation of trace lines in the cache is delayed on initial operation of the system to assure quality of the trace lines stored.
    Type: Application
    Filed: October 5, 2006
    Publication date: April 10, 2008
    Inventors: Gordon T. Davis, Richard W. Doing, John D. Jabusch, M. V. V. Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20080086596
    Abstract: A single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines. A mechanism is described for indexing into the cache, and selecting the desired line. Control is exercised over which lines are contained within the cache. Provision is made for selection between a trace line and a conventional line when both match during a tag compare step.
    Type: Application
    Filed: October 4, 2006
    Publication date: April 10, 2008
    Inventors: Gordon T. Davis, Richard W. Doing, John D. Jabusch, M. V. V. Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20080086595
    Abstract: A single unified level one instruction cache in which some lines may contain traces and other lines in the same congruence class may contain blocks of instructions consistent with conventional cache lines. Power is conserved by guiding access to lines stored in the cache and lowering cache clock speed relative to the central processor clock speed.
    Type: Application
    Filed: October 4, 2006
    Publication date: April 10, 2008
    Inventors: Gordon T. Davis, Richard W. Doing, John D. Jabusch, M. V. V. Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaye, Jeffrey R. Summers
  • Publication number: 20080077778
    Abstract: Register renaming as contemplated by this invention allows processor hardware to use a larger set of registers than the architected registers visible to the compiler. This larger set of registers is called the physical register file. Thus, dynamically renaming every compiler-suggested architected register to a microarchitecture-specific physical register, allows the processor to overcome name dependencies and the hazards (pipeline slowdowns) induced by name dependencies. The invention here described differs from prior renaming techniques in that it extracts significant benefit from renaming with a fraction of the number of physical registers previously used for this process. The invention therefore also simplifies the logic involved in supporting the use of the physical registers.
    Type: Application
    Filed: September 25, 2006
    Publication date: March 27, 2008
    Inventors: Gordon T. Davis, Richard W. Doing, John D. Jabusch, M V V Anil Krishna, Brett Olsson, Eric F. Robinson, Sumedh W. Sathaya, Jeffrey R. Summers