Patents by Inventor Larry William Woodman

Larry William Woodman 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: 6026475
    Abstract: A method and apparatus for dynamically updating virtual to physical address mappings in order to reduce cache thrashing is disclosed in an example computer system having a memory apportioned into a number of pages. A cache is included in the computer system to store a subset of the pages of memory. Each of the pages of memory is addressed by a physical address that includes a cache page address portion. The pages of cache memory are accessed using a cache page address, which corresponds to the cache page address portion of the physical address of a corresponding page of memory. The disclosed system monitors the activity of virtual addresses and uses the activity of virtual addresses to increment cache page address activity counters. The cache page address activity counters are monitored to identify those cache page addresses that are frequently being accessed within a process to identify potential performance problems, such as thrashing.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: February 15, 2000
    Assignee: Digital Equipment Corporation
    Inventor: Larry William Woodman
  • Patent number: 6016529
    Abstract: In a computer system, a data structure is provided in memory for storing one or more data files from an external device. The data files stored in the data structure are accessible by a number of processes executing in the computer system. The computer system includes a storage device such as a cache for storing data from a subset of pages of the memory. Each of the pages of the cache is referred to as a cache page, having an associated cache page address. A physical address is allocated for storing each page of a retrieved data file stored in the data structure such that a cache page address portion of the physical address is selected from the available cache page addresses. The physical address is further selected such that the cache page addresses are substantially evenly distributed amongst the pages of the retrieved data file and the data structure in order to minimize thrashing in the cache and enhance performance.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: January 18, 2000
    Assignee: Digital Equipment Corporation
    Inventor: Larry William Woodman
  • Patent number: 5996055
    Abstract: A method and apparatus for reclaiming a page of physical memory in a computer system for subsequent mappings to a virtual address is provided in a system wherein the physical memory is apportioned into a number of pages. The computer system includes a temporary storage device, such as a cache, for storing a subset of the pages in memory. Each of the pages stored in the cache are accessed using a cache page address. Virtual addresses are mapped to physical addresses responsive to monitoring use of the cache page addresses associated with the allocated physical addresses. According to the present invention, a page of physical memory is reclaimed such that a substantially even distribution of cache page addresses is maintained in physical addresses of both mapped and available pages of memory. Pages are originally placed on the clean list in response to characteristics of each page including the cache page address of the page.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: November 30, 1999
    Assignee: Digital Equipment Corporation
    Inventor: Larry William Woodman