Patents by Inventor Oded Cohn

Oded Cohn 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: 8285924
    Abstract: A cache control system is disclosed for use with data storage apparatus having a movably mounted storage element, such as a magnetic or optical disk and solid-state cache memory, in which the storage element is not at operating speed when data access has not occurred during a predetermined time period, comprising means arranged to access data stored on the storage element if a read or write request cannot be satisfied via access to the cache memory and a cache replacement mechanism for transferring data between the cache memory and the storage element to maintain consistency of data therebetween. The system is characterized in that the cache replacement mechanism performs data transfers between the cache memory and the storage element only while the storage element is at operating speed after a read or write request has given rise to an access to the storage element.
    Type: Grant
    Filed: December 27, 1994
    Date of Patent: October 9, 2012
    Inventors: Oded Cohn, Eliezer Dekel, Michael Rodeh
  • Patent number: 5734861
    Abstract: A log-structured array (LSA) includes a relatively large, non-volatile cache memory as well as a memory segment write buffer. The LSA cache memory contains both updated logical tracks received from the host system and also clean logical tracks read from direct access storage devices of the array. When the fraction of updated tracks in the cache memory exceeds a threshold value, updated tracks are moved from the LSA cache memory to the memory segment. With each modified track to be moved, adjacent modified tracks also are moved. The updated tracks are moved regardless of their location in the updated LRU list. Clean tracks in the LSA cache memory are moved into the memory segment as well, when additional clean tracks are needed in the cache memory. The clean tracks are selected from the bottom of the LSA cache clean track LRU list. Checking for adjacency also can occur at garbage collection time, performed in a background mode.
    Type: Grant
    Filed: December 12, 1995
    Date of Patent: March 31, 1998
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, Richard Lewis Mattson, Jaishankar Moothedath Menon
  • Patent number: 5659677
    Abstract: A data storage disk device for a RAID disk array is disclosed, comprising a rotatably mounted disk having a data storage surface; a first head for reading data from and writing data to the data storage surface; with a second head for reading data from the data storage surface; and control means for executing a write operation to a sector, said write operation including reading the contents of the sector via the second head for subsequent processing and writing new data to the sector via the first head, the first and second heads being arranged with respect to the data storage surface so that the new data can be written to the sector on the same revolution of the disk as the reading operation. The addition of a second head to the disk storage device improves performance of the disk device for RAID applications.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: August 19, 1997
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, Yoram Novick, Michael Rodeh, Alex Winokur
  • Patent number: 5606679
    Abstract: A method and apparatus for improving storage controller throughput and reducing unit control block contention when selecting a Utility Volume for servicing non-specific read requests. Throughput is increased by enabling the storage controller to service non-specific read requests issued against a Utility Volume which is not the same as the device associated with the data that the non-specific read is requesting. The Utility Volume is dynamically selected by considering the current loads on the available devices for both specific and non-specific processing. A Penalty Index is assigned to each volume, wherein the Penalty Index is a weighted average of the specific and non-specific processing. The device having the lowest Penalty Index is selected as the Utility Volume for a session. A Penalty Index evaluation is made at a Reference Point which is further enabled by a random clock to ensure that sessions do not likely pick the same Utility Volume.
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: February 25, 1997
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, William F. Micka, Yosef Moatti, Kenneth Nagin, Yoram Novick, Efaim Zeidner
  • Patent number: 5594900
    Abstract: A backup method for a computer database system comprising maintaining a mirrored copy of the database at a remote location is characterized in that updates to the remote database data are delayed for a delay time greater than or equal to the upper limit on the data communication delay between the local location and the remote location and updates to a remote log for the database are executed after corresponding updates to a local log without said delay. In this way a consistent copy of the database may be recovered from the mirrored copy of the database and the remote log after destruction of the database system.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: January 14, 1997
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, Kenneth Nagin, Yoram Novick, Alex Winokur
  • Patent number: 5493724
    Abstract: A method and apparatus for improving storage controller throughput when servicing non-specific read requests. Throughput is increased by enabling the storage controller to service non-specific read requests issued against a device address which is not the same as the device address associated with the data that the non-specific read is requesting. The device address associated with the data is thus free to be used for another I/O operation. When the device address used by the non-specific read is a non-busy type (that is, the device and/or data is not locked) then the throughput improvement is obtained by increasing the number of data requests that may be concurrently handled by the storage controller.
    Type: Grant
    Filed: April 1, 1993
    Date of Patent: February 20, 1996
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, William F. Micka, Kenneth M. Nagin, Yoram Novick, Udi N. Rotics, Alexander Winokur, Efraim Zeidner
  • Patent number: 5490269
    Abstract: A computer implemented method for speeding up the recursive most significant digit radix sorting of a set of record keys in which the keys are scanned for a shared or common prefix, coded according to the point in the key where they differ and the value of the differing digit, and processed such that during each dispersion phase the code words are used to speed processing by avoiding comparison matching of the prefixes, the recursive dispersion and collection phases continuing until singletons are reached. In the absence of shared prefixes the keys are normally recursively radix sorted.
    Type: Grant
    Filed: January 13, 1993
    Date of Patent: February 6, 1996
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, Shmuel Gal, Yona Hollander, Dafna Sheinwald
  • Patent number: 5448718
    Abstract: A data backup copying session on a data processing system is secured responsive to initiation of the data backup session by an application executing on a processing unit by generating a unique identifier for the data backup session. Thereafter, all member paths of a group of paths designated by the processing unit for communication between itself and the first storage subsystem are identified and associated with the data backup session. Access to the session is thereafter allowed only along a member path of the group of paths associated with the data backup session. The system and method of the invention further provide for fault recovery and protection against excessive demand on storage control unit memory.
    Type: Grant
    Filed: April 20, 1992
    Date of Patent: September 5, 1995
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, William F. Micka, Kenneth M. Nagin, Yoram Novick, Alexander Winokur
  • Patent number: 5408656
    Abstract: A method and system for efficiently accessing desired datasets among multiple datasets which are stored at specific data addresses within multiple storage subsystems which are coupled to a host system via a storage subsystem controller and a data channel. A data request is transmitted from the host system to the storage subsystems via the data channel. The data request specifies non-address attributes for desired datasets, such as boundary addresses for large data extents including many datasets or a request for all datasets modified since the occurrence of a specified event. The data request is then processed at the storage subsystem controller to determine a data address for each dataset within the storage subsystem which possess the desired attributes. Thereafter, the desired datasets are transmitted via the data channel to the host system in association with a specific address for each dataset.
    Type: Grant
    Filed: September 23, 1992
    Date of Patent: April 18, 1995
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, Michael H. Hartung, William F. Micka, Kenneth M. Nagin, Yoram Novick, Nimrod Rotics, Alexander Winokur, Efraim Zeidner
  • Patent number: 5379398
    Abstract: A method and system are disclosed for permitting high concurrency of access during backup copying of designated data stored within a storage subsystem which includes multiple storage devices coupled to the data processing system via a storage subsystem control unit having subsystem memory therein. Data within each storage device is accessed utilizing a Unique Control Block (UCB), which identifies a selected storage device, and an associated data retrieval command sequence which identifies the data to be accessed. Portions of the data copied to subsystem memory within the subsystem storage control unit as sidefiles from a first storage device may be accessed utilizing a Unique Control Block (UCB) associated with an alternate storage device by associating a selected data retrieval command sequence therewith which identifies the data as stored within the subsystem memory.
    Type: Grant
    Filed: April 20, 1992
    Date of Patent: January 3, 1995
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, Michael H. Hartung, John N. McCauley, Jr., William F. Micka, Claus W. Mikkelsen, Kenneth M. Nagin, Yoram Novick, Alexander Winokur
  • Patent number: 5241669
    Abstract: A method and system are disclosed for enhanced efficiency of backup copying of designated datasets stored within a plurality of storage devices coupled to the data processing system via a storage subsystem control unit having subsystem memory therein. Application execution within the data processing system is temporarily suspended long enough to form a dataset logical-to-physical system address concordance to be utilized to administer copying of the designated dataset. Thereafter, application initiated updates to uncopied portions of the designated datasets are temporarily deferred until sidefiles of the affected portions of the designated datasets are written to subsystem memory. The updates are then written to the storage subsystem. Portions of the designated datasets are then accessed and copied from the storage subsystem on a scheduled or opportunistic basis utilizing selected data retrieval command sequences.
    Type: Grant
    Filed: April 20, 1992
    Date of Patent: August 31, 1993
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, Michael H. Hartung, William F. Micka, John N. McCauley, Jr., Claus W. Mikkelsen, Kenneth M. Nagin
  • Patent number: RE37364
    Abstract: A method and system are disclosed for enhanced efficiency of backup copying of designated datasets stored within a plurality of storage devices coupled to the data processing system via a storage subsystem control unit having subsystem memory therein. Application execution within the data processing system is temporarily suspended long enough to form a dataset logical-to-physical system address concordance to be utilized to administer copying of the designated dataset. Thereafter, application initiated updates to uncopied portions of the designated datasets are temporarily deferred until sidefiles of the affected portions of the designated datasets are written to subsystem memory. The updates are then written to the storage subsystem. Portions of the designated datasets are then accessed and copied from the storage subsystem on a scheduled or opportunistic basis utilizing selected data retrieval command sequences.
    Type: Grant
    Filed: August 31, 1995
    Date of Patent: September 11, 2001
    Assignee: International Business Machines Corporation
    Inventors: Oded Cohn, Michael Howard Hartung, William Frank Micka, John Norbert McCauley, Jr., Claus William Mikkelsen, Kenneth Michael Nagin, Yoram Novick, Alexander Winokur