Patents by Inventor Ka Shan Choy

Ka Shan Choy 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: 8195881
    Abstract: Data is accessed in a multi-level hierarchical memory system. A request for data is received, including a virtual address for accessing the data. A translation buffer is queried to obtain an absolute address corresponding to the virtual address. Responsive to the translation buffer not containing an absolute address corresponding to the virtual address, the absolute address is obtained from a translation unit. A directory look-up is performed with the absolute address to determine whether a matching absolute address exists in the directory. A fetch request for the requested data is sent to a next level in the multi-level hierarchical memory system. Processing of the fetch request by the next level occurs in parallel with the directory lookup. The requested data is received in the primary cache to make the requested data available to be written to the primary cache.
    Type: Grant
    Filed: February 26, 2008
    Date of Patent: June 5, 2012
    Assignee: International Business Machines Corporation
    Inventors: Richard E. Bohn, Ka-shan Choy, Chung-Lung Kevin Shum, Aaron Tsai
  • Patent number: 7890700
    Abstract: A method, system, and computer program product for cross-invalidation handling in a multi-level private cache are provided. The system includes a processor. The processor includes a fetch address register logic in communication with a level 1 data cache, a level 1 instruction cache, a level 2 cache, and a higher level cache. The processor also includes a set of cross-invalidate snapshot counter implemented in the fetch address register. Each cross-invalidate snapshot counter tracks an amount of pending higher level cross-invalidations received before new data for the corresponding cache miss is returned from the higher-level cache. The processor also includes logic executing on the fetch address register for handling level 1 data cache misses and interfacing with the level 2 cache. In response to the new data, and upon determining that older cross-invalidations are pending, the new data is prevented from being used by the processor.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: February 15, 2011
    Assignee: International Business Machines Corporation
    Inventors: Ka Shan Choy, Jennifer A. Navarro, Chung-Lung Kevin Shum, Aaron Tsai
  • Publication number: 20090240889
    Abstract: A method, system, and computer program product for cross-invalidation handling in a multi-level private cache are provided. The system includes a processor. The processor includes a fetch address register logic in communication with a level 1 data cache, a level 1 instruction cache, a level 2 cache, and a higher level cache. The processor also includes a set of cross-invalidate snapshot counter implemented in the fetch address register. Each cross-invalidate snapshot counter tracks an amount of pending higher level cross-invalidations received before new data for the corresponding cache miss is returned from the higher-level cache. The processor also includes logic executing on the fetch address register for handling level 1 data cache misses and interfacing with the level 2 cache. In response to the new data, and upon determining that older cross-invalidations are pending, the new data is prevented from being used by the processor.
    Type: Application
    Filed: March 19, 2008
    Publication date: September 24, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Ka Shan Choy, Jennifer A. Navarro, Chung-Lung Kevin Shum, Aaron Tsai
  • Publication number: 20090216947
    Abstract: Data is accessed in a multi-level hierarchical memory system. A request for data is received, including a virtual address for accessing the data. A translation buffer is queried to obtain an absolute address corresponding to the virtual address. Responsive to the translation buffer not containing an absolute address corresponding to the virtual address, the absolute address is obtained from a translation unit. A directory look-up is performed with the absolute address to determine whether a matching absolute address exists in the directory. A fetch request for the requested data is sent to a next level in the multi-level hierarchical memory system. Processing of the fetch request by the next level occurs in parallel with the directory lookup. The requested data is received in the primary cache to make the requested data available to be written to the primary cache.
    Type: Application
    Filed: February 26, 2008
    Publication date: August 27, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Richard E. Bohn, Ka-shan Choy, Chung-Lung Kevin Shum, Aaron Tsai