Patents by Inventor Song Guen Yoon
Song Guen Yoon 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: 11966614Abstract: A system, method, and machine-readable storage medium for restoring a data object for a specified active time period are provided. In some embodiments, the method includes receiving, by a storage device from a client, a request specifying an active time period for a data object to remain stored on an accessible tier. The method also includes determining, by the storage device, that the active time period has elapsed. The method further includes responsive to a determination that the active time period has elapsed, sending, by the storage device, a request to a server storing the data object to move the data object from the accessible tier to an archive tier. Data objects that are stored on the accessible tier are accessible by the client, and data objects that are stored on the archive tier are inaccessible by the client.Type: GrantFiled: July 21, 2022Date of Patent: April 23, 2024Assignee: NetApp, Inc.Inventors: Alvis Yung, Song Guen Yoon, Raymond Yu Shun Mak, Chia-Chen Chu, Dheeraj Sangamkar, Robin Mahony
-
Patent number: 11861165Abstract: A system, method, and machine-readable storage medium for analyzing a state of a data object are provided. In some embodiments, the method includes receiving, at a storage device, a metadata request for the data object from a client. The data object is composed of a plurality of segments. The method also includes selecting a subset of the plurality of segments and obtaining a segment state for each segment of the subset. Each segment state indicates whether the respective segment is accessible via a backing store. The method further includes determining a most restrictive state of the one or more segment states and sending state information to the client in response to the metadata request, the state information being derived from the most restrictive state.Type: GrantFiled: December 30, 2021Date of Patent: January 2, 2024Assignee: NETAPP, INC.Inventors: Raymond Yu Shun Mak, Aditya Kalyanakrishnan, Song Guen Yoon, Emalayan Vairavanathan, Dheeraj Sangamkar, Chia-Chen Chu
-
Patent number: 11656962Abstract: Distributed storage systems frequently use a centralized metadata repository that stores metadata in an eventually consistent distributed database. However, a metadata repository cannot be relied upon for determining which erasure coded fragments are lost because of a storage node(s) failures. Instead, when recovering a failed storage node, a list of missing fragments is generated based on fragments stored in storage devices of available storage nodes. A storage node performing the recovery sends a request to one or more of the available storage nodes for a fragment list. The fragment list is generated, not based on a metadata database, but on scanning storage devices for fragments related to the failed storage node. The storage node performing the recovery merges retrieved lists to create a master list indicating fragments that should be regenerated for recovery of the failed storage node(s).Type: GrantFiled: April 4, 2022Date of Patent: May 23, 2023Assignee: NETAPP, INC.Inventors: Song Guen Yoon, Dheeraj Raghavender Sangamkar, Emalayan Vairavanathan
-
Publication number: 20220357870Abstract: A system, method, and machine-readable storage medium for restoring a data object for a specified active time period are provided. In some embodiments, the method includes receiving, by a storage device from a client, a request specifying an active time period for a data object to remain stored on an accessible tier. The method also includes determining, by the storage device, that the active time period has elapsed. The method further includes responsive to a determination that the active time period has elapsed, sending, by the storage device, a request to a server storing the data object to move the data object from the accessible tier to an archive tier. Data objects that are stored on the accessible tier are accessible by the client, and data objects that are stored on the archive tier are inaccessible by the client.Type: ApplicationFiled: July 21, 2022Publication date: November 10, 2022Inventors: Alvis Yung, Song Guen Yoon, Raymond Yu Shun Mak, Chia-Chen Chu, Dheeraj Sangamkar, Robin Mahony
-
Patent number: 11416156Abstract: A system, method, and machine-readable storage medium for restoring a data object for a specified active time period are provided. In some embodiments, the method includes receiving, by a storage device from a client, a request specifying an active time period for a data object to remain stored on an accessible tier. The method also includes determining, by the storage device, that the active time period has elapsed. The method further includes responsive to a determination that the active time period has elapsed, sending, by the storage device, a request to a server storing the data object to move the data object from the accessible tier to an archive tier. Data objects that are stored on the accessible tier are accessible by the client, and data objects that are stored on the archive tier are inaccessible by the client.Type: GrantFiled: February 24, 2020Date of Patent: August 16, 2022Assignee: NETAPP, INC.Inventors: Alvis Yung, Song Guen Yoon, Raymond Yu Shun Mak, Chia-Chen Chu, Dheeraj Sangamkar, Robin Mahony
-
Publication number: 20220229749Abstract: Distributed storage systems frequently use a centralized metadata repository that stores metadata in an eventually consistent distributed database. However, a metadata repository cannot be relied upon for determining which erasure coded fragments are lost because of a storage node(s) failures. Instead, when recovering a failed storage node, a list of missing fragments is generated based on fragments stored in storage devices of available storage nodes. A storage node performing the recovery sends a request to one or more of the available storage nodes for a fragment list. The fragment list is generated, not based on a metadata database, but on scanning storage devices for fragments related to the failed storage node. The storage node performing the recovery merges retrieved lists to create a master list indicating fragments that should be regenerated for recovery of the failed storage node(s).Type: ApplicationFiled: April 4, 2022Publication date: July 21, 2022Inventors: Song Guen Yoon, Dheeraj Raghavender Sangamkar, Emalayan Vairavanathan
-
Patent number: 11372738Abstract: Distributed storage systems frequently use a centralized metadata repository that stores metadata in an eventually consistent distributed database. However, a metadata repository cannot be relied upon for determining which erasure coded fragments are lost because of a storage node(s) failures. Instead, when recovering a failed storage node, a list of missing fragments is generated based on fragments stored in storage devices of available storage nodes. A storage node performing the recovery sends a request to one or more of the available storage nodes for a fragment list. The fragment list is generated, not based on a metadata database, but on scanning storage devices for fragments related to the failed storage node. The storage node performing the recovery merges retrieved lists to create a master list indicating fragments that should be regenerated for recovery of the failed storage node(s).Type: GrantFiled: December 12, 2019Date of Patent: June 28, 2022Assignee: NETAPP, INC.Inventors: Song Guen Yoon, Dheeraj Raghavender Sangamkar, Emalayan Vairavanathan
-
Publication number: 20220121364Abstract: A system, method, and machine-readable storage medium for analyzing a state of a data object are provided. In some embodiments, the method includes receiving, at a storage device, a metadata request for the data object from a client. The data object is composed of a plurality of segments. The method also includes selecting a subset of the plurality of segments and obtaining a segment state for each segment of the subset. Each segment state indicates whether the respective segment is accessible via a backing store. The method further includes determining a most restrictive state of the one or more segment states and sending state information to the client in response to the metadata request, the state information being derived from the most restrictive state.Type: ApplicationFiled: December 30, 2021Publication date: April 21, 2022Inventors: Raymond Yu Shun Mak, Aditya Kalyanakrishnan, Song Guen Yoon, Emalayan Vairavanathan, Dheeraj Sangamkar, Chia-Chen Chu
-
Patent number: 11243692Abstract: A system, method, and machine-readable storage medium for analyzing a state of a data object are provided. In some embodiments, the method includes receiving, at a storage device, a metadata request for the data object from a client. The data object is composed of a plurality of segments. The method also includes selecting a subset of the plurality of segments and obtaining a segment state for each segment of the subset. Each segment state indicates whether the respective segment is accessible via a backing store. The method further includes determining a most restrictive state of the one or more segment states and sending state information to the client in response to the metadata request, the state information being derived from the most restrictive state.Type: GrantFiled: March 20, 2019Date of Patent: February 8, 2022Assignee: NETAPP, INC.Inventors: Raymond Yu Shun Mak, Aditya Kalyanakrishnan, Song Guen Yoon, Emalayan Vairavanathan, Dheeraj Sangamkar, Chia-Chen Chu
-
Publication number: 20210263666Abstract: A system, method, and machine-readable storage medium for restoring a data object for a specified active time period are provided. In some embodiments, the method includes receiving, by a storage device from a client, a request specifying an active time period for a data object to remain stored on an accessible tier. The method also includes determining, by the storage device, that the active time period has elapsed. The method further includes responsive to a determination that the active time period has elapsed, sending, by the storage device, a request to a server storing the data object to move the data object from the accessible tier to an archive tier. Data objects that are stored on the accessible tier are accessible by the client, and data objects that are stored on the archive tier are inaccessible by the client.Type: ApplicationFiled: February 24, 2020Publication date: August 26, 2021Inventors: Alvis Yung, Song Guen Yoon, Raymond Yu Shun Mak, Chia-Chen Chu, Dheeraj Sangamkar, Robin Mahony
-
Patent number: 10817393Abstract: To ensure that there is an elected manager among storage nodes of an erasure coding group (“ECG”), an ECG manager (“ECGM”) election process is periodically performed among available storage nodes that are configured with the software to perform the services of an ECGM. When a storage node is activated, an ECGM process of the storage node begins executing and is assigned a process identifier (“PID”). A storage node can utilize a service query framework to identify other available storage nodes and retrieve their ECGM PIDs. The storage node then selects a PID according to a criterion and elects the storage node corresponding to the selected PID to be the acting ECGM. This process is performed periodically, so even if the acting ECGM storage node fails, a new ECGM is eventually selected from the available storage nodes.Type: GrantFiled: April 23, 2019Date of Patent: October 27, 2020Assignee: NETAPP, INC.Inventors: Dheeraj Raghavender Sangamkar, Song Guen Yoon, Emalayan Vairavanathan, Yi Zhang
-
Patent number: 10795789Abstract: To efficiently recover from a multiple storage node failure, a storage node concurrently restores data fragments to the multiple failed storage nodes, as opposed to restoring each node individually. In the VCS based storage technique, storage nodes are restored as part of an ECG repair process. For each ECG being repaired, a storage node performing the restoration process reads data fragments from active nodes in the ECG and generates new data fragments to replace any lost data fragments. The node then stores one of the new data fragments across each of the failed storage nodes. By concurrently restoring data fragments to each failed storage node, the data fragments needed to repair each ECG are only read once, thereby preserving disk operations and network bandwidth.Type: GrantFiled: July 2, 2019Date of Patent: October 6, 2020Assignee: NETAPP, INC.Inventors: Emalayan Vairavanathan, Dheeraj Raghavender Sangamkar, Song Guen Yoon, Yi Zhang
-
Publication number: 20200183587Abstract: A system, method, and machine-readable storage medium for analyzing a state of a data object are provided. In some embodiments, the method includes receiving, at a storage device, a metadata request for the data object from a client. The data object is composed of a plurality of segments. The method also includes selecting a subset of the plurality of segments and obtaining a segment state for each segment of the subset. Each segment state indicates whether the respective segment is accessible via a backing store. The method further includes determining a most restrictive state of the one or more segment states and sending state information to the client in response to the metadata request, the state information being derived from the most restrictive state.Type: ApplicationFiled: March 20, 2019Publication date: June 11, 2020Inventors: Raymond Yu Shun Mak, Aditya Kalyanakrishnan, Song Guen Yoon, Emalayan Vairavanathan, Dheeraj Sangamkar, Chia-Chen Chu
-
Publication number: 20200117560Abstract: Distributed storage systems frequently use a centralized metadata repository that stores metadata in an eventually consistent distributed database. However, a metadata repository cannot be relied upon for determining which erasure coded fragments are lost because of a storage node(s) failures. Instead, when recovering a failed storage node, a list of missing fragments is generated based on fragments stored in storage devices of available storage nodes. A storage node performing the recovery sends a request to one or more of the available storage nodes for a fragment list. The fragment list is generated, not based on a metadata database, but on scanning storage devices for fragments related to the failed storage node. The storage node performing the recovery merges retrieved lists to create a master list indicating fragments that should be regenerated for recovery of the failed storage node(s).Type: ApplicationFiled: December 12, 2019Publication date: April 16, 2020Inventors: Song Guen Yoon, Dheeraj Raghavender Sangamkar, Emalayan Vairavanathan
-
Patent number: 10558538Abstract: Distributed storage systems frequently use a centralized metadata repository that stores metadata in an eventually consistent distributed database. However, a metadata repository cannot be relied upon for determining which erasure coded fragments are lost because of a storage node(s) failures. Instead, when recovering a failed storage node, a list of missing fragments is generated based on fragments stored in storage devices of available storage nodes. A storage node performing the recovery sends a request to one or more of the available storage nodes for a fragment list. The fragment list is generated, not based on a metadata database, but on scanning storage devices for fragments related to the failed storage node. The storage node performing the recovery merges retrieved lists to create a master list indicating fragments that should be regenerated for recovery of the failed storage node(s).Type: GrantFiled: November 22, 2017Date of Patent: February 11, 2020Assignee: NETAPP, INC.Inventors: Song Guen Yoon, Dheeraj Raghavender Sangamkar, Emalayan Vairavanathan
-
Publication number: 20200034256Abstract: To efficiently recover from a multiple storage node failure, a storage node concurrently restores data fragments to the multiple failed storage nodes, as opposed to restoring each node individually. In the VCS based storage technique, storage nodes are restored as part of an ECG repair process. For each ECG being repaired, a storage node performing the restoration process reads data fragments from active nodes in the ECG and generates new data fragments to replace any lost data fragments. The node then stores one of the new data fragments across each of the failed storage nodes. By concurrently restoring data fragments to each failed storage node, the data fragments needed to repair each ECG are only read once, thereby preserving disk operations and network bandwidth.Type: ApplicationFiled: July 2, 2019Publication date: January 30, 2020Inventors: Emalayan Vairavanathan, Dheeraj Raghavender Sangamkar, Song Guen Yoon, Yi Zhang
-
Patent number: 10503621Abstract: To ensure that there is an elected manager among storage nodes of an erasure coding group (“ECG”), an ECG manager (“ECGM”) election process is periodically performed among available storage nodes that are configured with the software to perform the services of an ECGM. When a storage node is activated, an ECGM process of the storage node begins executing and is assigned a process identifier (“PID”). A storage node can utilize a service query framework to identify other available storage nodes and retrieve their ECGM PIDs. The storage node then selects a PID according to a criterion and elects the storage node corresponding to the selected PID to be the acting ECGM. This process is performed periodically, so even if the acting ECGM storage node fails, a new ECGM is eventually selected from the available storage nodes.Type: GrantFiled: May 8, 2017Date of Patent: December 10, 2019Assignee: NETAPP, INC.Inventors: Dheeraj Raghavender Sangamkar, Song Guen Yoon, Emalayan Vairavanathan, Yi Zhang
-
Publication number: 20190251009Abstract: To ensure that there is an elected manager among storage nodes of an erasure coding group (“ECG”), an ECG manager (“ECGM”) election process is periodically performed among available storage nodes that are configured with the software to perform the services of an ECGM. When a storage node is activated, an ECGM process of the storage node begins executing and is assigned a process identifier (“PID”). A storage node can utilize a service query framework to identify other available storage nodes and retrieve their ECGM PIDs. The storage node then selects a PID according to a criterion and elects the storage node corresponding to the selected PID to be the acting ECGM. This process is performed periodically, so even if the acting ECGM storage node fails, a new ECGM is eventually selected from the available storage nodes.Type: ApplicationFiled: April 23, 2019Publication date: August 15, 2019Inventors: Dheeraj Raghavender Sangamkar, Song Guen Yoon, Emalayan Vairavanathan, Yi Zhang
-
Patent number: 10353740Abstract: To efficiently recover from a multiple storage node failure, a storage node concurrently restores data fragments to the multiple failed storage nodes, as opposed to restoring each node individually. In the VCS based storage technique, storage nodes are restored as part of an ECG repair process. For each ECG being repaired, a storage node performing the restoration process reads data fragments from active nodes in the ECG and generates new data fragments to replace any lost data fragments. The node then stores one of the new data fragments across each of the failed storage nodes. By concurrently restoring data fragments to each failed storage node, the data fragments needed to repair each ECG are only read once, thereby preserving disk operations and network bandwidth.Type: GrantFiled: May 8, 2017Date of Patent: July 16, 2019Assignee: NETAPP, INC.Inventors: Emalayan Vairavanathan, Dheeraj Raghavender Sangamkar, Song Guen Yoon, Yi Zhang
-
Publication number: 20190155708Abstract: Distributed storage systems frequently use a centralized metadata repository that stores metadata in an eventually consistent distributed database. However, a metadata repository cannot be relied upon for determining which erasure coded fragments are lost because of a storage node(s) failures. Instead, when recovering a failed storage node, a list of missing fragments is generated based on fragments stored in storage devices of available storage nodes. A storage node performing the recovery sends a request to one or more of the available storage nodes for a fragment list. The fragment list is generated, not based on a metadata database, but on scanning storage devices for fragments related to the failed storage node. The storage node performing the recovery merges retrieved lists to create a master list indicating fragments that should be regenerated for recovery of the failed storage node(s).Type: ApplicationFiled: November 22, 2017Publication date: May 23, 2019Inventors: Song Guen Yoon, Dheeraj Raghavender Sangamkar, Emalayan Vairavanathan