Patents by Inventor Vinay Srihari
Vinay Srihari 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).
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Publication number: 20070168319Abstract: Techniques are provided for managing caches in a system with multiple caches that may contain different copies of the same data item. Specifically, techniques are provided for coordinating the write-to-disk operations performed on such data items to ensure that older versions of the data item are not written over newer versions, and to reduce the amount of processing required to recover after a failure. Various approaches are provided in which a master is used to coordinate with the multiple caches to cause a data item to be written to persistent storage. Techniques are also provided for managing checkpoints associated with the caches, where the checkpoints are used to determine the position at which to begin processing recovery logs in the event of a failure.Type: ApplicationFiled: February 20, 2007Publication date: July 19, 2007Applicant: Oracle International CorporationInventors: Sashikanth Chandrasekaran, Roger Bamford, William Bridge, David Brower, Neil MacNaughton, Wilson Chan, Vinay Srihari
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Patent number: 7200623Abstract: Techniques are provided for managing caches in a system with multiple caches that may contain different copies of the same data item. Specifically, techniques are provided for coordinating the write-to-disk operations performed on such data items to ensure that older versions of the data item are not written over newer versions, and to reduce the amount of processing required to recover after a failure. Various approaches are provided in which a master is used to coordinate with the multiple caches to cause a data item to be written to persistent storage. Techniques are also provided for managing checkpoints associated with the caches, where the checkpoints are used to determine the position at which to begin processing recovery logs in the event of a failure.Type: GrantFiled: March 4, 2002Date of Patent: April 3, 2007Assignee: Oracle International Corp.Inventors: Sashikanth Chandrasekaran, Roger J. Bamford, William H. Bridge, David Brower, Neil MacNaughton, Wilson Wai Shun Chan, Vinay Srihari
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Publication number: 20060200497Abstract: Techniques are provided for detecting lost writes so that data corruption can be avoided. According to one technique, lost writes are detected by comparing version numbers that are indicated in redo log entries with version numbers that are indicated in corresponding blocks in a standby database. According to one technique, which may be used in conjunction with the above technique, lost writes are detected by logging read operations that occur relative to a primary database, and comparing version numbers that are indicated in read log entries with version numbers that are indicated in corresponding blocks in a standby database. According to one technique, lost writes are detected by comparing, in response to read operations, (a) version numbers that are stored in a persistent in-memory cache with (b) version numbers that are indicated in corresponding blocks that are read from a primary database.Type: ApplicationFiled: March 3, 2005Publication date: September 7, 2006Inventors: Wei Hu, Mark Dilman, J. Lee, Juan Loaiza, Vinay Srihari
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Publication number: 20060195648Abstract: Techniques are provided for managing caches in a system with multiple caches that may contain different copies of the same data item. Specifically, techniques are provided for coordinating the write-to-disk operations performed on such data items to ensure that older versions of the data item are not written over newer versions, and to reduce the amount of processing required to recover after a failure. Various approaches are provided in which a master is used to coordinate with the multiple caches to cause a data item to be written to persistent storage. Techniques are also provided for managing checkpoints associated with the caches, where the checkpoints are used to determine the position at which to begin processing recovery logs in the event of a failure.Type: ApplicationFiled: April 17, 2006Publication date: August 31, 2006Applicant: ORACLE INTERNATIONAL CORPORATIONInventors: Sashikanth Chandrasekaran, Roger Bamford, William Bridge, David Brower, Neil MacNaughton, Wilson Chan, Vinay Srihari
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Patent number: 7065540Abstract: Techniques are provided for managing caches in a system with multiple caches that may contain different copies of the same data item. Specifically, techniques are provided for coordinating the write-to-disk operations performed on such data items to ensure that older versions of the data item are not written over newer versions, and to reduce the amount of processing required to recover after a failure. Various approaches are provided in which a master is used to coordinate with the multiple caches to cause a data item to be written to persistent storage. Techniques are also provided for managing checkpoints associated with the caches, where the checkpoints are used to determine the position at which to begin processing recovery logs in the event of a failure.Type: GrantFiled: March 4, 2002Date of Patent: June 20, 2006Assignee: Oracle International CorporationInventors: Sashikanth Chandrasekaran, Roger J. Bamford, William H. Bridge, David Brower, Neil MacNaughton, Wilson Wai Shun Chan, Vinay Srihari
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Publication number: 20060101033Abstract: Each of a plurality of Worker processes are allowed to perform any and all of the following tasks involving logged work items: (1) reading a subset of the work items from a log; (2) sequentially ordering work items for corresponding data objects; (3) applying a sequentially ordered set of work items to a corresponding data object; and (4) transmitting a subset of work items to a Worker process running on another database server in a cluster, if necessary. These tasks can be performed concurrently, at will, and as available, by the Worker processes. An improved checkpointing technique eliminates the need for the Worker processes to get to a synchronization point and stop. Instead, a Coordinator process examines the current state of progress of the Worker processes and computes a past point in the sequence of work items at which all work items before that point have been completely processed, and records this point as the checkpoint.Type: ApplicationFiled: November 5, 2004Publication date: May 11, 2006Applicant: ORACLE INTERNATIONAL CORPORATIONInventors: Wei Hu, Yunrui Li, Vinay Srihari, Ramana Yerneni
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Patent number: 7039773Abstract: An improved method, mechanism, and system for implementing, generating, and maintaining records, such as redo records and redo logs in a database system, are disclosed. Multiple sets of records may be created and combined into a partially ordered (or non-ordered) group of records, which are later collectively ordered or sorted as needed to create an fully ordered set of records. With respect to a database system, redo generation bottleneck is minimized by providing multiple in-memory redo buffers that are available to hold redo records generated by multiple threads of execution. When the in-memory redo buffers are written to a persistent storage medium, no specific ordering needs to be specified with respect to the redo records from the different in-memory redo buffers. While the collective group of records may not be ordered, the written-out redo records may be partially ordered based upon the ordered redo records from within individual in-memory redo buffers.Type: GrantFiled: April 29, 2003Date of Patent: May 2, 2006Assignee: Oracle International CorporationInventors: Wei Ming Hu, Juan R. Loaiza, Roger J. Bamford, Vikram Joshi, Arvind Nithrakashyap, Tudor Bosman, Vinay Srihari, Alok Pareek
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Publication number: 20050065907Abstract: Techniques are provided for managing caches in a system with multiple caches that may contain different copies of the same data item. Specifically, techniques are provided for coordinating the write-to-disk operations performed on such data items to ensure that older versions of the data item are not written over newer versions, and to reduce the amount of processing required to recover after a failure. Various approaches are provided in which a master is used to coordinate with the multiple caches to cause a data item to be written to persistent storage. Techniques are also provided for managing checkpoints associated with the caches, where the checkpoints are used to determine the position at which to begin processing recovery logs in the event of a failure.Type: ApplicationFiled: October 12, 2004Publication date: March 24, 2005Applicant: ORACLE CORPORATIONInventors: Sashikanth Chandrasekaran, Roger Bamford, William Bridge, David Brower, Neil MacNaughton, Wilson Wai Chan, Vinay Srihari
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Publication number: 20040221116Abstract: An improved method, mechanism, and system for implementing, generating, and maintaining records, such as redo records and redo logs in a database system, are disclosed. Multiple sets of records may be created and combined into a partially ordered (or non-ordered) group of records, which are later collectively ordered or sorted as needed to create an fully ordered set of records. With respect to a database system, redo generation bottleneck is minimized by providing multiple in-memory redo buffers that are available to hold redo records generated by multiple threads of execution. When the in-memory redo buffers are written to a persistent storage medium, no specific ordering needs to be specified with respect to the redo records from the different in-memory redo buffers. While the collective group of records may not be ordered, the written-out redo records may be partially ordered based upon the ordered redo records from within individual in-memory redo buffers.Type: ApplicationFiled: April 29, 2003Publication date: November 4, 2004Applicant: Oracle International CorporationInventors: Wei Ming Hu, Juan R. Loaiza, Roger J. Bamford, Vikram Joshi, Arvind Nithrakashyap, Tudor Bosman, Vinay Srihari, Alok Pareek
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Publication number: 20020099729Abstract: Techniques are provided for managing caches in a system with multiple caches that may contain different copies of the same data item. Specifically, techniques are provided for coordinating the write-to-disk operations performed on such data items to ensure that older versions of the data item are not written over newer versions, and to reduce the amount of processing required to recover after a failure. Various approaches are provided in which a master is used to coordinate with the multiple caches to cause a data item to be written to persistent storage. Techniques are also provided for managing checkpoints associated with the caches, where the checkpoints are used to determine the position at which to begin processing recovery logs in the event of a failure.Type: ApplicationFiled: March 4, 2002Publication date: July 25, 2002Applicant: ORACLE CORPORATIONInventors: Sashikanth Chandrasekaran, Roger J. Bamford, William H. Bridge, David Brower, Neil MacNaughton, Wilson Wai Shun Chan, Vinay Srihari
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Publication number: 20020095403Abstract: Techniques are provided for managing caches in a system with multiple caches that may contain different copies of the same data item. Specifically, techniques are provided for coordinating the write-to-disk operations performed on such data items to ensure that older versions of the data item are not written over newer versions, and to reduce the amount of processing required to recover after a failure. Various approaches are provided in which a master is used to coordinate with the multiple caches to cause a data item to be written to persistent storage. Techniques are also provided for managing checkpoints associated with the caches, where the checkpoints are used to determine the position at which to begin processing recovery logs in the event of a failure.Type: ApplicationFiled: March 4, 2002Publication date: July 18, 2002Inventors: Sashikanth Chandrasekaran, Roger J. Bamford, William H. Bridge, David Brower, Neil MacNaughton, Wilson Wai Shun Chan, Vinay Srihari