Patents by Inventor Joon Chang

Joon Chang 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).

  • Publication number: 20120066278
    Abstract: Management of a file hierarchy for a clustered file system can be distributed across nodes of the cluster. A cluster file hierarchy is accessed to determine location of a file in response to a request to write to a file. A first node maintains the cluster file hierarchy. It is determined that management of a fileset object, which represents a fileset that includes the file, has been delegated to a second node based, at least in part, on said accessing the cluster file hierarchy. A node file hierarchy maintained by the second node is accessed responsive to determining the delegation. The cluster file hierarchy represents filesets of the clustered file system and the node hierarchy represents a subset of one or more of the filesets. Location of the file is determined based, at least in part, on said accessing the node file hierarchy.
    Type: Application
    Filed: September 10, 2010
    Publication date: March 15, 2012
    Applicant: International Business Machines Corporation
    Inventors: Janet E. Adkins, Joon Chang, David J. Craft, Gokul B. Kandiraju, Manoj N. Kumar
  • Publication number: 20120066191
    Abstract: Embodiments include a method comprising transmitting from a node of a plurality of nodes within a clustered file system provides concurrent file I/O access for files, to write access a region of a file. The method includes receiving an authorization to write access the region without a lock to preclude access of the region by other nodes, if at least one physical section in a machine-readable medium has been allocated for storage of the region by the server. The method includes receiving the authorization to write access the region with the lock to preclude access of the region by the other nodes, if the at least one physical section in the machine-readable medium has not been allocated for storage of the region by the server. Responsive to receiving the authorization to write access, metadata is transmitted for storage into the at least one physical section in the machine-readable medium.
    Type: Application
    Filed: September 10, 2010
    Publication date: March 15, 2012
    Applicant: International Business Machines Corporation
    Inventors: Joon Chang, Robert K. Gjertsen, Ninad S. Palsule
  • Publication number: 20120066182
    Abstract: Some embodiments of the inventive subject matter allow a redirect-on-write file system to continue processing file transactions while writing a snapshot to persistent storage. Thus, embodiments do not block file transactions while flushing snapshots to persistent storage. To avoid blocking, some embodiments the file system can maintain two snapshot generations. The first snapshot generation is the snapshot being written to persistent storage. The second snapshot generation may reside in main memory, and store data for file transactions occurring after the file system began writing the first snapshot generation.
    Type: Application
    Filed: September 10, 2010
    Publication date: March 15, 2012
    Applicant: International Business Machines Corporation
    Inventors: Joon Chang, David J. Craft, Gokul B. Kandiraju, Manoj N. Kumar
  • Publication number: 20120066183
    Abstract: After a clone file is created from a file, a write request targeting the clone file can be handled. It is determined that the write request indicates the clone file that was cloned from a file in a first fileset. The clone file is of a second fileset and a clustered file system comprises the first fileset and the second fileset. A data block of the clone file affected by the write request is determined. It is then determined that the data block at a current location cannot be modified. The write request is implemented with respect to the data block at a different location.
    Type: Application
    Filed: September 10, 2010
    Publication date: March 15, 2012
    Applicant: International Business Machines Corporation
    Inventors: Janet E. Adkins, Joon Chang, David J. Craft, Manoj N. Kumar, Ninad S. Palsule
  • Publication number: 20120054152
    Abstract: A client node on which a file system is mounted can be configured to efficiently handle content access requests after a snapshot is created. The client node can maintain generation numbers at a data block, a file, and a fileset level to determine whether a data block is part of a snapshot generation and consequently whether the data block is writable in a current generation. Data block mappings and write access permissions associated with the data blocks need not be revoked at the client node prior to creating the snapshot. Cached data block mappings can be accessed to identify data blocks for servicing a read request. The data block can be updated in place if the data block is not part of the snapshot generation. The write request can be serviced at a new data block if the data block is part of the snapshot generation.
    Type: Application
    Filed: August 26, 2010
    Publication date: March 1, 2012
    Applicant: International Business Machines Corporation
    Inventors: Janet E. Adkins, Joon Chang, Robert K. Gjertsen, Ninad S. Palsule
  • Publication number: 20120005162
    Abstract: A method, data processing system, and computer program product for managing data. A processor unit copies a data structure within a hierarchy of data structures to form a copy of the data structure. The data structure belongs to a level within a plurality of levels in the hierarchy of data structures. The processor unit associates an identifier with the data structure within the hierarchy of data structures. The processor unit increments a portion of the identifier for the data structure in response to copying the data structure to form the copy of the data structure and associating the identifier with the data structure within the hierarchy of data structures. The portion of the identifier that is incremented is based on the level within the plurality of levels in which the data structure is located.
    Type: Application
    Filed: June 30, 2010
    Publication date: January 5, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Janet E. Adkins, Joon Chang, David J. Craft
  • Publication number: 20110193589
    Abstract: An on-chip sensor measures dynamic power supply noise, such as voltage droop, on a semiconductor chip. In-situ logic is employed, which is sensitive to noise present on the power supply of functional logic of the chip. Exemplary functional logic includes a microprocessor, adder, and/or other functional logic of the chip. The in-situ logic performs some operation, and the amount of time required for performing that operation (i.e., the operational delay) is sensitive to noise present on the power supply. Thus, by evaluating the operational delay of the in-situ logic, the amount of noise present on the power supply can be measured.
    Type: Application
    Filed: February 10, 2010
    Publication date: August 11, 2011
    Applicant: QUALCOMM INCORPORATED
    Inventors: Lew G. Chua-Eoan, Boris Andreev, Christopher Phan, Amirali Shayan, Xiaohua Kong, Mikhail Popovich, Mauricio Calle, IK-Joon Chang
  • Patent number: 7958325
    Abstract: A temporary file is identified. The temporary file includes a data block containing a first file image. A determination is made whether the temporary block has been included in a previous snapshot. Responsive to receiving a modification of the temporary block that has been included in the previous snapshot, a modified first image is created. The modified image is stored in the original file block, and the original image is copied to a newly allocated block. The original first block is updated to include a reference to the second block.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: June 7, 2011
    Assignee: International Business Machines Corporation
    Inventors: Janet Elizabeth Adkins, Joon Chang
  • Patent number: 7950360
    Abstract: A continuous variable valve lift apparatus according to an exemplary embodiment of the present invention includes an input cam disposed to an input shaft, a first shaft in parallel with the input shaft, a first link connected with the first shaft, a second link rotatably connected to the first link, an output cam that is rotatably connected with the second link and configured with a contact portion contacting the input cam, a second shaft disposed to the output cam parallel with the input shaft, at least one valve unit that is opened and closed by the output cam, and a control part that controls a position of the second shaft.
    Type: Grant
    Filed: June 20, 2008
    Date of Patent: May 31, 2011
    Assignee: Hyundai Motor Company
    Inventors: Young Hong Kwak, Kiyoung Kwon, Jin Kook Kong, Kyoung Joon Chang
  • Patent number: 7921081
    Abstract: In one embodiment, at least one snapshot thread manages a point in time snapshot of a file system stored within the space allocated to the file system. The snapshot thread tracks, for at least one block of the plurality of blocks of the file system, a separate entry in a snapshot map specifying if each at least one block is newly allocated following the creation of the point in time snapshot and specifying an addressed location of a snapshot copy of the at least one block if copied. Separately, a file system handling thread tracks a mapping of an allocation state of each of said plurality of blocks of the file system.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: April 5, 2011
    Assignee: International Business Machines Corporation
    Inventors: Janet E. Adkins, Joon Chang
  • Patent number: 7918202
    Abstract: A variable valve apparatus includes a high lift cam and a low lift cam in parallel with the high lift cam. A tappet body includes a high lift tappet body that constantly contacts the high lift cam, and a low lift tappet body that is disposed in the high lift tappet body and selectively contacts the low lift cam. An inner column is connected with a valve and reciprocally disposed within the low lift tappet body. A supporting member is disposed below the tappet body. A lost motion elastic member is disposed between the supporting member and the tappet body for supplying restoring force to the tappet body. A first connector selectively connects the high lift tappet body and the low lift tappet body. A second connector selectively connects the low lift tappet body and the inner column.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: April 5, 2011
    Assignee: Hyundai Motor Company
    Inventors: Young Hong Kwak, Kiyoung Kwon, Ki Uk Shin, Jin Kook Kong, Kyoung Joon Chang
  • Patent number: 7905207
    Abstract: A variable valve lift apparatus may include a camshaft having an input cam, a rocker arm shaft disposed in parallel with the camshaft with a distance therebetween, a shaft carrier with a camshaft and a rocker arm shaft, a rocker arm that is mounted on the rocker arm shaft with a first roller contacting the input cam, a first link connected to the rocker arm, an amplification lever with a middle portion thereof connected to the first link and the shaft carrier, a second link connected to the amplification lever, an output cam mounted on the camshaft, one side of the output cam connected to the second link, and a profile portion formed at an exterior circumference thereof, a variable driveshaft rotating the shaft carrier by a predetermined angle, and a valve moved by the profile portion with rotation of the output cam.
    Type: Grant
    Filed: November 20, 2008
    Date of Patent: March 15, 2011
    Assignee: Hyundai Motor Company
    Inventors: Eun Ho Lee, Young Hong Kwak, Kiyoung Kwon, Jin Kook Kong, Soo Hyung Woo, Kyoung Joon Chang
  • Patent number: 7836863
    Abstract: A variable lift apparatus of an engine for a vehicle may include a camshaft in which a cam is formed, a swing arm one side of which is supported by a supporting portion and another side of which operates a valve, an output arm including a roller press portion extended in one direction and a rotating arm extended in another direction, a first roller disposed in the connecting portion in which the rotating arm and the roller press portion are connected and that contacts the cam, a second roller disposed in the swing arm and contacting a roller contacting surface, a variable link connected with a lower end side of the rotating arm protruding in a lower side of the output arm by a hinge shaft and moves the hinge shaft according to a guide slot formed in a guide and a variable rotation shaft for operating the variable link.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: November 23, 2010
    Assignee: Hyundai Motor Company
    Inventors: Young Hong Kwak, Kiyoung Kwon, Jin Kook Kong, Kyoung Joon Chang
  • Patent number: 7823552
    Abstract: A continuous variable valve lift apparatus includes an input cam disposed on an input shaft, a valve opening/closing portion, and a rocker arm rotating shaft. A rocker arm rotates around the rocker arm rotating shaft corresponding to a rotation of the input cam. An output cam is disposed at an end of the rocker arm, and opens and closes the valve opening/closing portion. A control portion controls a position of the rocker arm rotating shaft.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: November 2, 2010
    Assignee: Hyundai Motor Company
    Inventors: Kiyoung Kwon, Young Hong Kwak, Ki Uk Shin, Kyoung Joon Chang, Jin Kook Kong
  • Publication number: 20100250493
    Abstract: One embodiment is for using a sparse file as a clone. The method includes creating, by an application associated with a computer system, a snapshot of a file, such as an individual file, a collection of files, file system, directories, and so forth. Further, the method includes requesting, by the application, a clone of that created snapshot. Further still, the method includes generating, by the application, an empty sparse having at least one inode identifying the empty sparse file as the clone and pointing to the snapshot associated with the clone. Thereby, the requested clone is created using the created sparse file, which begins as an empty sparse file.
    Type: Application
    Filed: March 31, 2009
    Publication date: September 30, 2010
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Janet E. Adkins, Joon Chang, Manoj N. Kumar, Grover H. Neuman
  • Patent number: 7805471
    Abstract: The present invention provides a computer implemented method for truncating a file in a file system. The file system receives a request to truncate a file to a target size, the file having a first inode. The file system creates a second inode to a transient directory, wherein the second inode holds a plurality of in-progress entries. The file system sets a target size in the first inode. The file system writes a truncate entry to a journal, the truncate entry comprising a predetermined size. The file system truncates the file by up to the predetermined size. The file system determines that the file is above the target size. Responsive to a determination that the file is above the target size, the file system repeats the truncating step and the determining step. Responsive to a determination that the file is not above the target size, the file system applies the in-progress entries from the transient directory.
    Type: Grant
    Filed: January 14, 2008
    Date of Patent: September 28, 2010
    Assignee: International Business Machines, Corporation
    Inventors: Shashidhar Bomma, Joon Chang, Ramesh Veeramalla, Sreenivas Makineedi
  • Patent number: 7789053
    Abstract: A continuous variable valve lift apparatus according to an exemplary embodiment of the present invention includes a camshaft, an input cam disposed to the camshaft, a variable lever that is rotably connected to the camshaft and includes a first arm including a first connecting shaft and a second arm including a second connecting shaft, a first link rotating around the first connecting shaft corresponding to a rotation of the input cam, an output cam rotating around the camshaft, a valve opening/closing portion that is opened and closed corresponding to a rotation of the output cam, and a connecting portion that is disposed for the output cam to rotate corresponding to a rotation of the first link.
    Type: Grant
    Filed: April 23, 2008
    Date of Patent: September 7, 2010
    Assignees: Hyundai Motor Company, Kia Motors Corporation
    Inventors: Jin Kook Kong, Won Geun Lee, Kyoung Joon Chang, Kiyoung Kwon, Young Hong Kwak, Ki Uk Shin, Eun Ho Lee, Young Nam Kim
  • Patent number: 7778961
    Abstract: Methods, systems, and products for delayed deletion of extended attributes associated with a file in a file system are provided. Embodiments include identifying a file to delete, moving an extended attribute directory associated with the file to a background deletion directory, deleting the file, and deleting in the background the extended attribute directory. Some embodiments also include deleting an ACL associated with the file.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: August 17, 2010
    Assignee: International Business Machines Corporation
    Inventors: Joon Chang, Zachary M. Loafman, Jean-Philippe Sugarbroad
  • Publication number: 20100100831
    Abstract: Methods to allow, suppress, or reformulate a presentation of a UI element invoked by a computer program are provided. One method includes applying an administrator-configurable heuristic to determine whether to allow a native presentation of the UI element, to suppress the native presentation of the UI element, or to enable a reformulated presentation of the UI element. The method further includes one or more of suppressing and reformulating the UI element in accordance with a determination of the heuristic.
    Type: Application
    Filed: October 17, 2008
    Publication date: April 22, 2010
    Applicant: MICROSOFT CORPORATION
    Inventors: Chris Whytock, Maxim Oustiougov, Thibaut Vial, Joon Chang
  • Patent number: 7702662
    Abstract: A system for managing a file system. In response to a user selecting an image of the file system to perform a rollback operation, each data block in the file system that is owned by the image is searched for. Then, it is determined whether a data block owned by the image is marked in a first map and a second map. In response to determining that the data block owned by the image is marked in the first map and the second map, the data block is marked in a third map. In response to determining that the data block owned by the image is marked in the third map, a new data block is allocated in the file system. Subsequently, data from the data block owned by the image is copied to the new data block in the file system prior to performing the rollback operation to avoid a collision that causes data corruption.
    Type: Grant
    Filed: May 16, 2007
    Date of Patent: April 20, 2010
    Assignee: International Business Machines Corporation
    Inventors: Janet Elizabeth Adkins, Joon Chang