公开(公告)号：US20140365734A1

公开(公告)日：2014-12-11

申请号：US13914001

申请日：2013-06-10

Applicant: Oracle International Corporation

Inventor： William H. Bridge, JR. ,  Paul Loewenstein ,  Mark A. Luttrell

IPC: G06F12/08

CPC classification number: G06F12/0891 ,  G06F9/52 ,  G06F12/0804 ,  G06F12/0815 ,  G06F12/0831 ,  G06F12/0833 ,  G06F12/084 ,  G06F12/0868

Abstract: Systems and methods for reliably using data storage media. Multiple processors are configured to access a persistent memory. For a given data block corresponding to a write access request from a first processor to the persistent memory, a cache controller prevents any read access of a copy of the given data block in an associated cache. The cache controller prevents any read access while detecting an acknowledgment that the given data block is stored in the persistent memory is not yet received. Until the acknowledgment is received, the cache controller allows write access of the copy of the given data block in the associated cache only for a thread in the first processor that originally sent the write access request. The cache controller invalidates any copy of the given data block in any cache levels below the associated cache.

Abstract translation: 可靠地使用数据存储介质的系统和方法。 多个处理器被配置为访问持久存储器。 对于对应于从第一处理器到持久存储器的写访问请求的给定数据块，高速缓存控制器防止在相关联的高速缓存中的给定数据块的副本的任何读访问。 高速缓存控制器在检测到尚未接收到持久存储器中存储给定数据块的确认时防止任何读访问。 在接收到确认之前，高速缓存控制器允许仅对最初发送写访问请求的第一处理器中的线程对相关联的高速缓存中的给定数据块的副本进行写访问。 高速缓存控制器使相关高速缓存下的任何缓存级别的给定数据块的任何副本无效。

公开(公告)号：US20150363123A1

公开(公告)日：2015-12-17

申请号：US14833432

申请日：2015-08-24

Applicant: Oracle International Corporation

Inventor： William H. Bridge, JR. ,  Prasad Bagal ,  Lavina Jain ,  Rajiv Wickremesinghe ,  Darshan Nagarajappa ,  Richard L. Long

IPC: G06F3/06 ,  G06F11/20

CPC classification number: G06F3/0617 ,  G06F3/0653 ,  G06F3/0683 ,  G06F11/2053 ,  G06F11/2094 ,  G06F11/3433

Abstract: Techniques are provided for assigning read requests to storage devices in a manner that reduces the likelihood that any storage device will become overloaded or underutilized. Specifically, a read-request handler assigns read requests that are directed to each particular item among the storage devices that have copies of the item based on how busy each of those storage devices is. Consequently, even though certain storage devices may have copies of the same item, there may be times during which one storage device is assigned a disproportionate number of the reads of the item because the other storage device is busy with read requests for other items, and there may be other times during which other storage device is assigned a disproportionate number of the reads of the item because the one storage device is busy with read request for other items. Various techniques for estimating the busyness of storage devices are provided, including fraction-based estimates, interval-based estimates, and the response-time-based estimates. Techniques for smoothing those estimates, and for handicapping devices, are also provided.

Abstract translation: 提供了以减少任何存储设备将变得过载或未充分利用的可能性的方式将读请求分配给存储设备的技术。 具体地说，读取请求处理程序根据这些存储设备的忙碌来分配针对具有项目副本的存储设备中的每个特定项目的读取请求。 因此，尽管某些存储设备可能具有相同项目的副本，但是由于另一个存储设备忙于对其他项目的读取请求，所以可能存在一个存储设备被分配了不成比例的该项目的读取的次数，以及 可能存在其他存储设备被分配了不成比例数量的项目的其他时间，因为一个存储设备忙于对其他项目的读取请求。 提供了用于估计存储设备的繁忙性的各种技术，包括基于分数的估计，基于间隔的估计和基于响应时间的估计。 还提供了用于平滑这些估计的技术和用于障碍装置的技术。

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：US20210081372A1

公开(公告)日：2021-03-18

申请号：US16812833

申请日：2020-03-09

Applicant: Oracle International Corporation

Inventor： J. William Lee ,  William H. Bridge, JR. ,  Ankur Kemkar ,  Vipin Gokhale ,  Sivaram Prasad Soma ,  Vishvesh Mohanarangam Selvakumaar ,  Juan R. Loaiza ,  Wei-Ming Hu ,  Neil J.S. MacNaughton ,  Adam Y. Lee

IPC: G06F16/182 ,  G06F16/16 ,  G06F12/02 ,  G06F12/123 ,  G06F9/4401 ,  G06F9/52 ,  G06F9/50

Abstract: Techniques herein store database blocks (DBBs) in byte-addressable persistent memory (PMEM) and prevent tearing without deadlocking or waiting. In an embodiment, a computer hosts a DBMS. A reader process of the DBMS obtains, without locking and from metadata in PMEM, a first memory address for directly accessing a current version, which is a particular version, of a DBB in PMEM. Concurrently and without locking: a) the reader process reads the particular version of the DBB in PMEM, and b) a writer process of the DBMS replaces, in the metadata in PMEM, the first memory address with a second memory address for directly accessing a new version of the DBB in PMEM. In an embodiment, a computer performs without locking: a) storing, in PMEM, a DBB, b) copying into volatile memory, or reading, an image of the DBB, and c) detecting whether the image of the DBB is torn.

公开(公告)号：US20150286649A1

公开(公告)日：2015-10-08

申请号：US14243792

申请日：2014-04-02

Applicant: Oracle International Corporation

Inventor： Yunrui Li ,  William H. Bridge, JR.

IPC: G06F17/30

CPC classification number: G06F17/30088 ,  G06F17/30377

Abstract: Techniques are described herein for making a clean file snapshot of a target file. The techniques may be applied to a single target file, to a set of target files, or to an entire database The techniques involve transitioning the target file through a series of states. During each state, particular actions are performed and/or prevented. In the final state of each approach, a clean file snapshot of the target file exists. Transitioning through the states, only one of which does not allow new changes to be made to the target file, allows the database to remain online and available to a greater extent than is possible with an approach that prevents database changes for the duration of the clean file snapshot creation operation.

Abstract translation: 这里描述了用于制作目标文件的干净文件快照的技术。 这些技术可以应用于单个目标文件，一组目标文件或整个数据库。这些技术涉及通过一系列状态转换目标文件。 在每个状态期间，执行和/或防止特定动作。 在每种方法的最终状态下，存在目标文件的干净的文件快照。 通过状态转换，只有其中一个不允许对目标文件进行新的更改，允许数据库在更大程度上保持在线，并且可用于在清理期间阻止数据库更改的方法。 文件快照创建操作。

公开(公告)号：US20140096145A1

公开(公告)日：2014-04-03

申请号：US13778307

申请日：2013-02-27

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Kathirgamar Aingaran ,  William H. Bridge, JR. ,  Garret F. Swart ,  Sumti Jairath ,  John G. Johnson

IPC: G06F9/54

CPC classification number: G06F9/30065 ,  G06F9/381 ,  G06F9/3851 ,  G06F9/3867 ,  G06F9/546 ,  G06F12/0804 ,  G06F12/082 ,  G06F12/12 ,  G06F12/1408 ,  G06F12/1475 ,  G06F13/102 ,  G06F13/362 ,  G06F13/4068 ,  G06F15/17331 ,  G06F15/7889 ,  G06F17/30324 ,  G06F17/30442 ,  G06F17/30483 ,  G06F17/30495 ,  G06F17/30498 ,  G06F17/30501 ,  G06F17/30519 ,  G06F17/30578 ,  G06F17/30595 ,  G06F17/30867 ,  G06F21/6209 ,  H04L69/14 ,  Y02D10/14 ,  Y02D10/151 ,  Y02D10/45

Abstract: A method and apparatus for sending and receiving messages between nodes on a compute cluster is provided. Communication between nodes on a compute cluster, which do not share physical memory, is performed by passing messages over an I/O subsystem. Typically, each node includes a synchronization mechanism, a thread ready to receive connections, and other threads to process and reassemble messages. Frequently, a separate queue is maintained in memory for each node on the I/O subsystem sending messages to the receiving node. Such overhead increases latency and limits message throughput. Due to a specialized coprocessor running on each node, messages on an I/O subsystem are sent, received, authenticated, synchronized, and reassembled at a faster rate and with lower latency. Additionally, the memory structure used may reduce memory consumption by storing messages from multiple sources in the same memory structure, eliminating the need for per-source queues.

Abstract translation: 提供了一种用于在计算集群上的节点之间发送和接收消息的方法和装置。 通过在I / O子系统上传递消息来执行不共享物理内存的计算集群上的节点之间的通信。 通常，每个节点包括同步机制，准备好接收连接的线程以及处理和重新组合消息的其他线程。 通常，I / O子系统中的每个节点向存储器中维护单独的队列，向接收节点发送消息。 这种开销增加了延迟并限制了消息吞吐量。 由于在每个节点上运行的专用协处理器，I / O子系统上的消息以更快的速率和更低的延迟被发送，接收，认证，同步和重新组装。 此外，所使用的存储器结构可以通过在相同存储器结构中存储来自多个源的消息来减少存储器消耗，从而消除对每个源队列的需要。