Patents by Inventor Hangwei Qian

Hangwei Qian 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: 10503423
    Abstract: In response to a request for accessing a file stored in a storage system, data objects associated with the file are retrieved from a storage device of the storage system. The data objects of the file are cached in a cache memory. An access sequence of the cached data objects within the file is determined based on metadata of the file, where the access sequence represents a sequential order in time of accessing the cached data objects within the file. In response to a request for cache space reclamation, one or more cached data objects are identified whose next access is a farthest in time from a data object currently being accessed amongst the cached data objects based on the access sequence of the data objects. The identified data objects are evicted from the cache memory whose next access is a farthest amongst the cached data objects.
    Type: Grant
    Filed: May 17, 2017
    Date of Patent: December 10, 2019
    Assignee: EMC IP Holding Company LLC
    Inventors: Frederick Douglis, Windsor W. Hsu, Hangwei Qian
  • Patent number: 9684469
    Abstract: Data objects of a file are cached in a cache memory of a storage system. An access sequence of the cached data objects is determined based on metadata of the file. In response to a request for cache space reclamation, a data object is evicted from the cache memory whose next access is a farthest amongst the cached data objects based on the access sequence of the data objects.
    Type: Grant
    Filed: April 30, 2012
    Date of Patent: June 20, 2017
    Assignee: EMC IP Holding Company LLC
    Inventors: Frederick Douglis, Windsor W. Hsu, Hangwei Qian
  • Patent number: 9389965
    Abstract: A request is received to read a portion of a file from the storage system. In response to the request, future requests to the file are predicted based in part on the received request and metadata of the file. Access of a subsequent portion of the file is optimized based on the predicted future requests and the data contained in the portion of the file is then returned.
    Type: Grant
    Filed: April 30, 2012
    Date of Patent: July 12, 2016
    Assignee: EMC Corporation
    Inventors: Frederick Douglis, Windsor W. Hsu, Hangwei Qian
  • Patent number: 9110792
    Abstract: Data objects of a file are cached in a cache memory of a storage system, where the data objects of the file are accessed sequentially via access windows in a chain. It is estimated whether a next access of a data object of the file likely occurs in which of the access windows using respective bloom filters associated with the access windows. In response to a request for cache space reclamation, a data object is evicted from the cache memory that will be likely accessed in a farthest access window in the chain from a current access window based on the estimation.
    Type: Grant
    Filed: April 30, 2012
    Date of Patent: August 18, 2015
    Assignee: EMC Corporation
    Inventors: Frederick Douglis, Windsor W. Hsu, Hangwei Qian