Patents by Inventor Wayne I. Yamamoto

Wayne I. Yamamoto 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: 6976125
    Abstract: One embodiment of the present invention provides a system for predicting hot spots in a cache memory. Upon receiving a memory operation at the cache, the system determines a target location within the cache for the memory operation. Once the target location is determined, the system increments a counter associated with the target location. If the counter reaches a pre-determined threshold value, the system generates a signal indicating that the target location is a hot spot in the cache memory.
    Type: Grant
    Filed: January 29, 2003
    Date of Patent: December 13, 2005
    Assignee: Sun Microsystems, Inc.
    Inventors: Sudarshan Kadambi, Vijay Balakrishnan, Wayne I. Yamamoto
  • Patent number: 6948032
    Abstract: One embodiment of the present invention provides a system that uses a hot spot cache to alleviate the performance problems caused by hot spots in cache memories, wherein the hot spot cache stores lines that are evicted from hot spots in the cache. Upon receiving a memory operation at the cache, the system performs a lookup for the memory operation in both the cache and the hot spot cache in parallel. If the memory operation is a read operation that causes a miss in the cache and a hit in the hot spot cache, the system reads a data line for the read operation from the hot spot cache, writes the data line to the cache, performs the read operation on the data line in the cache, and then evicts the data line from the hot spot cache.
    Type: Grant
    Filed: January 29, 2003
    Date of Patent: September 20, 2005
    Assignee: Sun Microsystems, Inc.
    Inventors: Sudarshan Kadambi, Vijay Balakrishnan, Wayne I. Yamamoto
  • Patent number: 6934830
    Abstract: One embodiment of the present invention provides a system that reduces the time required to access registers from a register file within a processor. During operation, the system receives an instruction to be executed, wherein the instruction identifies at least one operand to be accessed from the register file. Next, the system looks up the operands in a register pane, wherein the register pane is smaller and faster than the register file and contains copies of a subset of registers from the register file. If the lookup is successful, the system retrieves the operands from the register pane to execute the instruction. Otherwise, if the lookup is not successful, the system retrieves the operands from the register file, and stores the operands into the register pane. This triggers the system to reissue the instruction to be executed again, so that the re-issued instruction retrieves the operands from the register pane.
    Type: Grant
    Filed: September 26, 2002
    Date of Patent: August 23, 2005
    Assignee: Sun Microsystems, Inc.
    Inventors: Sudarshan Kadambi, Adam R. Talcott, Wayne I. Yamamoto
  • Publication number: 20040148469
    Abstract: One embodiment of the present invention provides a system for predicting hot spots in a cache memory. Upon receiving a memory operation at the cache, the system determines a target location within the cache for the memory operation. Once the target location is determined, the system increments a counter associated with the target location. If the counter reaches a pre-determined threshold value, the system generates a signal indicating that the target location is a hot spot in the cache memory.
    Type: Application
    Filed: January 29, 2003
    Publication date: July 29, 2004
    Inventors: Sudarshan Kadambi, Vijay Balakrishnan, Wayne I. Yamamoto
  • Publication number: 20040148465
    Abstract: One embodiment of the present invention provides a system that uses a hot spot cache to alleviate the performance problems caused by hot spots in cache memories, wherein the hot spot cache stores lines that are evicted from hot spots in the cache. Upon receiving a memory operation at the cache, the system performs a lookup for the memory operation in both the cache and the hot spot cache in parallel. If the memory operation is a read operation that causes a miss in the cache and a hit in the hot spot cache, the system reads a data line for the read operation from the hot spot cache, writes the data line to the cache, performs the read operation on the data line in the cache, and then evicts the data line from the hot spot cache.
    Type: Application
    Filed: January 29, 2003
    Publication date: July 29, 2004
    Inventors: Sudarshan Kadambi, Vijay Balakrishnan, Wayne I. Yamamoto
  • Patent number: 6725338
    Abstract: A method of optimizing speculative address load processing by a microprocessor includes identifying a speculative load, marking the speculative load, determining whether a miss occurs for the speculative load, and preventing use of the marked speculative load by the microprocessor if a miss occurs. A method of optimizing speculative address load processing by a microprocessor includes identifying a speculative load, marking the speculative load, inserting the marked speculative load into a load miss queue, determining whether a miss occurs for the speculative load, and preventing the load miss queue from committing the marked speculative load to cache if a miss occurs.
    Type: Grant
    Filed: November 19, 2001
    Date of Patent: April 20, 2004
    Assignee: Sun Microsystems, Inc.
    Inventors: Christopher A. Gomez, Wayne I. Yamamoto
  • Publication number: 20040064680
    Abstract: One embodiment of the present invention provides a system that reduces the time required to access registers from a register file within a processor. During operation, the system receives an instruction to be executed, wherein the instruction identifies at least one operand to be accessed from the register file. Next, the system looks up the operands in a register pane, wherein the register pane is smaller and faster than the register file and contains copies of a subset of registers from the register file. If the lookup is successful, the system retrieves the operands from the register pane to execute the instruction. Otherwise, if the lookup is not successful, the system retrieves the operands from the register file, and stores the operands into the register pane. This triggers the system to reissue the instruction to be executed again, so that the re-issued instruction retrieves the operands from the register pane.
    Type: Application
    Filed: September 26, 2002
    Publication date: April 1, 2004
    Inventors: Sudarshan Kadambi, Adam R. Talcott, Wayne I. Yamamoto
  • Publication number: 20020062208
    Abstract: A method and apparatus of visualizing events within a microprocessor include simulating the operation of a microprocessor for a set of instructions, generating the internal state information from the simulation and graphically displaying an execution behavior based on the internal state information. The graphical display represents a flow of the instructions through an internal pipeline in the microprocessor. Execution behavior is selectively displayed based on type of behavior and clock cycle the execution occurred during on the microprocessor. A log of the execution behavior of the set of instructions on the microprocessor is created. The set of instructions is created from a graphical display of selectable instructions.
    Type: Application
    Filed: November 19, 2001
    Publication date: May 23, 2002
    Inventors: Christopher A. Gomez, Wayne I. Yamamoto
  • Publication number: 20020062426
    Abstract: A method of optimizing speculative address load processing by a microprocessor includes identifying a speculative load, marking the speculative load, determining whether a miss occurs for the speculative load, and preventing use of the marked speculative load by the microprocessor if a miss occurs. A method of optimizing speculative address load processing by a microprocessor includes identifying a speculative load, marking the speculative load, inserting the marked speculative load into a load miss queue, determining whether a miss occurs for the speculative load, and preventing the load miss queue from committing the marked speculative load to cache if a miss occurs.
    Type: Application
    Filed: November 19, 2001
    Publication date: May 23, 2002
    Inventors: Christopher A. Gomez, Wayne I. Yamamoto