公开(公告)号：US20230050727A1

公开(公告)日：2023-02-16

申请号：US17974152

申请日：2022-10-26

Applicant: Oracle International Corporation

Inventor： Jesse Kamp ,  Allison L. Holloway ,  Meichun Hsu ,  Hideaki Kimura ,  Boris Klots ,  Vasudha Krishnaswamy ,  Kartik Kulkarni ,  Teck Hua Lee ,  Yunrui Li ,  Aurosish Mishra ,  Ajit Mylavarapu ,  Sukhada Pendse ,  Garret F. Swart ,  Shasank K. Chavan ,  Tirthankar Lahiri ,  Juan R. Loaiza

IPC: G06F16/22 ,  G06F16/27 ,  G06F16/21 ,  G06F16/174 ,  G06F16/18 ,  G06F16/23 ,  G06F16/11

Abstract: A shared-nothing database system is provided in which parallelism and workload balancing are increased by assigning the rows of each table to “slices”, and storing multiple copies (“duplicas”) of each slice across the persistent storage of multiple nodes of the shared-nothing database system. When the data for a table is distributed among the nodes of a shared-nothing system in this manner, requests to read data from a particular row of the table may be handled by any node that stores a duplica of the slice to which the row is assigned. For each slice, a single duplica of the slice is designated as the “primary duplica”. All DML operations (e.g. inserts, deletes, updates, etc.) that target a particular row of the table are performed by the node that has the primary duplica of the slice to which the particular row is assigned. The changes made by the DML operations are then propagated from the primary duplica to the other duplicas (“secondary duplicas”) of the same slice.

公开(公告)号：US11347678B2

公开(公告)日：2022-05-31

申请号：US16055978

申请日：2018-08-06

Applicant: Oracle International Corporation

Inventor： Tirthankar Lahiri ,  Juan R. Loaiza ,  Garret F. Swart ,  Jesse Kamp ,  Avneesh Pant ,  Hideaki Kimura

IPC: G06F9/54 ,  G06F15/173 ,  G06F15/167 ,  G06F9/455

Abstract: Techniques are provided to allow more sophisticated operations to be performed remotely by machines that are not fully functional. Operations that can be performed reliably by a machine that has experienced a hardware and/or software error are referred to herein as Remote Direct Memory Operations or “RDMOs”. Unlike RDMAs, which typically involve trivially simple operations such as the retrieval of a single value from the memory of a remote machine, RDMOs may be arbitrarily complex. The techniques described herein can help applications run without interruption when there are software faults or glitches on a remote system with which they interact.

公开(公告)号：US20220114192A1

公开(公告)日：2022-04-14

申请号：US17123405

申请日：2020-12-16

Applicant: Oracle International Corporation

Inventor： William H. Bridge, JR. ,  David Brower ,  Meichun Hsu ,  Boris Klots ,  Neil J S Macnaughton, JR. ,  Ajit Mylavarapu ,  Umesh Panchaksharaiah ,  Garret F. Swart ,  Tirthankar Lahiri ,  Juan R. Loaiza

IPC: G06F16/27 ,  G06F16/901 ,  G06F15/173

Abstract: A shared-nothing database system is provided in which parallelism and workload balancing are increased by assigning the rows of each table to “slices”, and storing multiple copies (“duplicas”) of each slice across the persistent storage of multiple nodes of the shared-nothing database system. When the data for a table is distributed among the nodes of a shared-nothing system in this manner, requests to read data from a particular row of the table may be handled by any node that stores a duplica of the slice to which the row is assigned. For each slice, a single duplica of the slice is designated as the “primary duplica”. All DML operations (e.g. inserts, deletes, updates, etc.) that target a particular row of the table are performed by the node that has the primary duplica of the slice to which the particular row is assigned. The changes made by the DML operations are then propagated from the primary duplica to the other duplicas (“secondary duplicas”) of the same slice.

公开(公告)号：US20220114058A1

公开(公告)日：2022-04-14

申请号：US17137745

申请日：2020-12-30

Applicant: Oracle International Corporation

Inventor： Ajit Mylavarapu ,  Vasudha Krishnaswamy ,  Sukhada Pendse ,  Solmaz Kolahi ,  Ankita Kumar ,  Garret F. Swart ,  Tirthankar Lahiri ,  Juan R. Loaiza

IPC: G06F11/14 ,  G06F16/22

Abstract: A shared-nothing database system is provided in which parallelism and workload balancing are increased by assigning the rows of each table to “slices”, and storing multiple copies (“duplicas”) of each slice across the persistent storage of multiple nodes of the shared-nothing database system. When the data for a table is distributed among the nodes of a shared-nothing system in this manner, requests to read data from a particular row of the table may be handled by any node that stores a duplica of the slice to which the row is assigned. For each slice, a single duplica of the slice is designated as the “primary duplica”. All DML operations (e.g. inserts, deletes, updates, etc.) that target a particular row of the table are performed by the node that has the primary duplica of the slice to which the particular row is assigned. The changes made by the DML operations are then propagated from the primary duplica to the other duplicas (“secondary duplicas”) of the same slice.

公开(公告)号：US10803039B2

公开(公告)日：2020-10-13

申请号：US15606322

申请日：2017-05-26

Applicant: Oracle International Corporation

Inventor： Siddharth Teotia ,  Krishna Kunchithapadam ,  Jesse Kamp ,  Tirthankar Lahiri ,  Michael J. Gleeson ,  Juan R. Loaiza ,  Garret F. Swart ,  Neil J. S. MacNaughton ,  Kam Shergill

IPC: G06F12/1045 ,  G06F15/173 ,  G06F16/22 ,  G06F16/907

Abstract: Techniques are provided for enabling a requesting entity to retrieve data that is managed by a database server instance from the volatile memory of a server machine that is executing the database server instance. The techniques allow the requesting entity to retrieve the data from the volatile memory of the host server machine without involving the database server instance in the retrieval operation. Because the retrieval does not involve the database server instance, the retrieval may succeed even when the database server instance has stalled or become unresponsive. In addition, direct retrieval of data using the techniques described herein will often be faster and more efficient than retrieval of the same information through conventional interaction with the database server instance.

公开(公告)号：US10719446B2

公开(公告)日：2020-07-21

申请号：US15693273

申请日：2017-08-31

Applicant: Oracle International Corporation

Inventor： Juan R. Loaiza ,  J. William Lee ,  Wei-Ming Hu ,  Kothanda Umamageswaran ,  Neil J. S. MacNaughton ,  Adam Y. Lee

IPC: G06F3/06 ,  G06F11/20 ,  G06F11/10 ,  G06F16/27 ,  G06F16/13 ,  G06F12/0873 ,  G06F16/172 ,  G06F12/0868 ,  G06F12/0866

Abstract: A method and apparatus for implementing a buffer cache for a persistent file system in non-volatile memory is provided. A set of data is maintained in one or more extents in non-volatile random-access memory (NVRAM) of a computing device. At least one buffer header is allocated in dynamic random-access memory (DRAM) of the computing device. In response to a read request by a first process executing on the computing device to access one or more first data blocks in a first extent of the one or more extents, the first process is granted direct read access of the first extent in NVRAM. A reference to the first extent in NVRAM is stored in a first buffer header. The first buffer header is associated with the first process. The first process uses the first buffer header to directly access the one or more first data blocks in NVRAM.

公开(公告)号：US20190294558A1

公开(公告)日：2019-09-26

申请号：US16435101

申请日：2019-06-07

Applicant: Oracle International Corporation

Inventor： Siddharth Teotia ,  Krishna Kunchithapadam ,  Tirthankar Lahiri ,  Jesse Kamp ,  Michael J. Gleeson ,  Juan R. Loaiza ,  Garret F. Swart ,  Neil J.S. MacNaughton ,  Kam Shergill

IPC: G06F12/1018 ,  G06F16/2453 ,  G06F16/22 ,  G06F12/126 ,  G06F12/0864 ,  G06F12/0868 ,  G06F12/128 ,  G06F16/901

Abstract: A hashing scheme includes a cache-friendly, latchless, non-blocking dynamically resizable hash index with constant-time lookup operations that is also amenable to fast lookups via remote memory access. Specifically, the hashing scheme provides each of the following features: latchless reads, fine grained lightweight locks for writers, non-blocking dynamic resizability, cache-friendly access, constant-time lookup operations, amenable to remote memory access via RDMA protocol through one sided read operations, as well as non-RDMA access.

公开(公告)号：US10303788B2

公开(公告)日：2019-05-28

申请号：US15253630

申请日：2016-08-31

Applicant: Oracle International Corporation

Inventor： Kartik Kulkarni ,  Juan R. Loaiza ,  Vivekanandhan Raja ,  Kothanda Umamageswaran ,  Sanket Hase ,  Vasudha Krishnaswamy ,  Tirthankar Lahiri

IPC: G06F17/30

Abstract: A minimum value (MV) is computed for start timestamps that each correspond to an uncommitted transaction. In an embodiment, the MV is computed for a pluggable database that is open on at least first and second instances of a database. The MV is computed for the first instance as of a first current timestamp (CT). The MV and the first CT are communicated to a second instance that has a second CT. If the first and second CTs are equal, the second instance store the MV. If the first CT is bigger, the second CT also becomes equal to the first CT. If the first CT is smaller, the MV is discarded, and the first CT becomes equal to the second CT. In an embodiment, if the MV remains unchanged for a predetermined time period, a start timestamp corresponding to the MV is advanced to a current or future timestamp.

公开(公告)号：US10229161B2

公开(公告)日：2019-03-12

申请号：US14489221

申请日：2014-09-17

Applicant: Oracle International Corporation

Inventor： Sarat B. Kakarla ,  Jia Shi ,  Selcuk Aya ,  Kothanda Umamageswaran ,  Juan R. Loaiza

IPC: G06F17/30

Abstract: Approaches, techniques, and mechanisms are disclosed for improved caching in database systems that deal with multiple data access patterns, such as in database systems that interface with both OLTP and Data Warehouse clients. A cache is deployed between a database server and a storage system that stores data units. Some of the data units accessed by the database server are buffered within the cache. The data units may be associated with data access patterns, such as a random data access pattern or a scan data access pattern, in accordance with which the database server is or appears to be accessing the data units. A processor selects when to cache data units accessed by the database server, based at least on the associated data access patterns. Recent access counts may also be stored for the data units, and may further be utilized to select when to cache data units.

公开(公告)号：US09361232B2

公开(公告)日：2016-06-07

申请号：US13839251

申请日：2013-03-15

Applicant: Oracle International Corporation

Inventor： Kothanda Umamageswaran ,  Juan R. Loaiza ,  Umesh Panchaksharaiah ,  Alexander Tsukerman ,  Timothy L. Shetler ,  Bharat C. V. Baddepudi ,  Boris Erlikhman ,  Kiran B. Goyal ,  Nilesh Choudhury ,  Susy Fan ,  Poojan Kumar ,  Selcuk Aya ,  Sue-Kyoung Lee

IPC: G06F12/084 ,  G06F12/08 ,  G06F17/30

CPC classification number: G06F12/084 ,  G06F12/0811 ,  G06F12/0866 ,  G06F12/0888 ,  G06F17/3048 ,  G06F17/30492

Abstract: Techniques are provided for using an intermediate cache to provide some of the items involved in a scan operation, while other items involved in the scan operation are provided from primary storage. Techniques are also provided for determining whether to service an I/O request for an item with a copy of the item that resides in the intermediate cache based on factors such as a) an identity of the user for whom the I/O request was submitted, b) an identity of a service that submitted the I/O request, c) an indication of a consumer group to which the I/O request maps, or d) whether the intermediate cache is overloaded. Techniques are also provided for determining whether to store items in an intermediate cache in response to the items being retrieved, based on logical characteristics associated with the requests that retrieve the items.

Abstract translation: 提供了使用中间缓存来提供扫描操作中涉及的一些项目的技术，而从主存储器提供涉及扫描操作的其他项目。 还提供了用于基于以下因素来确定是否对具有驻留在中间高速缓存中的项目的副本的项目的I / O请求进行服务的技术，例如：a）向其提交I / O请求的用户的身份 ，b）提交I / O请求的服务的身份，c）I / O请求所映射的消费者组的指示，或d）中间缓存是否过载。 还提供了基于与检索项目的请求相关联的逻辑特征来确定是否将项目存储在中间高速缓存中以响应于正被检索的项目的技术。