公开(公告)号：US20030115501A1

公开(公告)日：2003-06-19

申请号：US10348673

申请日：2003-01-21

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Roger J. Bamford

IPC: H04L001/22

CPC classification number: H04L1/16 ,  H04L1/1685 ,  H04L1/1848 ,  H04L47/10 ,  H04L69/16 ,  H04L69/164

Abstract: A method and mechanism is described for reliably transmitting messages over an unreliable transport mechanism. A sender transmits a first message over an unreliable mechanism to a receiver, and a second message that identifies the first is transported over a reliable transport mechanism to the receiver. When the receiver receives the second message, the receiver determines whether it has received the first message. If not, the receiver requests retransmission of the first message.

Abstract translation: 描述了通过不可靠的传输机制可靠地发送消息的方法和机制。 发送方通过不可靠机制向接收方发送第一消息，并且识别第一消息的第二消息通过可靠的传输机制传送到接收方。 当接收机接收到第二消息时，接收机确定它是否已经接收到第一消息。 如果不是，则接收机请求重发第一条消息。

公开(公告)号：US20040215639A1

公开(公告)日：2004-10-28

申请号：US10831401

申请日：2004-04-23

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Roger J. Bamford ,  Sashikanth Chandrasekaran ,  Angelo Pruscino

IPC: G06F007/00

CPC classification number: G06F17/30575 ,  G06F9/5083 ,  Y10S707/972 ,  Y10S707/99944

Abstract: Various techniques are described for improving the performance of a shared-nothing database system in which at least two of the nodes that are running the shared-nothing database system have shared access to a disk. Specifically, techniques are provided for changing the ownership of data in a shared-nothing database dynamically, based on factors such as which node would be the most efficient owner relative to the performance of a particular operation. Once determined, the ownership of the data may be changed permanently to the new owner, or temporarily for the duration of the particular operation.

Abstract translation: 描述了用于改善无共享数据库系统的性能的各种技术，其中运行无共享数据库系统的至少两个节点具有对盘的共享访问。 具体地说，提供了基于诸如哪个节点相对于特定操作的性能来说最有效的所有者的因素来动态地改变无共享数据库中的数据的所有权的技术。 一旦确定，数据的所有权可以永久地更改为新的所有者，或者在特定操作期间临时更改。

公开(公告)号：US20040148289A1

公开(公告)日：2004-07-29

申请号：US10718875

申请日：2003-11-21

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Roger J. Bamford ,  Sashikanth Chandrasekaran ,  Angelo Pruscino

IPC: G06F007/00

CPC classification number: G06F17/30575 ,  G06F17/30377 ,  Y10S707/99956

Abstract: Techniques are provided for handling distributed transactions in shared-nothing database systems where one or more of the nodes have access to a shared persistent storage. Rather than coordinate the distributed transaction using a two-phase commit protocol, the coordinator of the distributed transaction uses a one-phase commit protocol with those participants that have access to the transaction status information maintained by the coordinator. The transaction status information may reside, for example, in the redo log of the coordinator. In the case that the coordinator fails, those participants can determine the state of the distributed transaction based on information stored on the shared disk. In addition, the coordinator is able to determine whether it is possible to commit the distributed transaction based on information that is stored on the shared disk by the participants, without those participants entering a formal nullpreparednull state.

Abstract translation: 提供了用于在无共享数据库系统中处理分布式事务的技术，其中一个或多个节点可以访问共享永久存储。 分布式事务的协调器不是使用两阶段提交协议来协调分布式事务，而是与那些能够访问协调器维护的事务状态信息的参与者使用一阶段提交协议。 事务状态信息可以驻留在例如协调器的重做日志中。 在协调器失败的情况下，这些参与者可以基于存储在共享磁盘上的信息来确定分布式事务的状态。 此外，协调器能够根据参与者在共享磁盘上存储的信息来确定是否可以提交分布式事务，而不需要参与者进入正式的“准备”状态。

公开(公告)号：US20040117345A1

公开(公告)日：2004-06-17

申请号：US10665062

申请日：2003-09-17

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Roger J. Bamford ,  Sashikanth Chandrasekaran ,  Angelo Pruscino

IPC: G06F007/00

CPC classification number: G06F17/3038 ,  G06F17/30575 ,  Y10S707/99943

Abstract: Various techniques are described for improving the performance of a shared-nothing database system in which at least two of the nodes that are running the shared-nothing database system have shared access to a disk. Specifically, techniques are provided for changing the ownership of data in a shared-nothing database without changing the location of the data on persistent storage. Because the persistent storage location for the data is not changed during a transfer of ownership of the data, ownership can be transferred more freely and with less of a performance penalty than would otherwise be incurred by a physical relocation of the data. Various techniques are also described for providing fast run-time reassignment of ownership. Because the reassignment can be performed during run-time, the shared-nothing system does not have to be taken offline to perform the reassignment. Further, the techniques describe how the reassignment can be performed with relatively fine granularity, avoiding the need to perform bulk reassignment of large amounts of data across all nodes merely to reassign ownership of a few data items on one of the nodes.

Abstract translation: 描述了用于改善无共享数据库系统的性能的各种技术，其中运行无共享数据库系统的至少两个节点具有对盘的共享访问。 具体来说，提供了用于在不改变永久存储器上的数据的位置的情况下改变无共享数据库中的数据的所有权的技术。 由于数据的持有存储位置在数据的所有权转移期间没有改变，因此所有权可以更自由地传送，而不会因数据的物理重定位而导致的性能损失更少。 还描述了用于提供所有权的快速运行时重新分配的各种技术。 因为可以在运行时执行重新分配，所以无需共享系统就不必脱机执行重新分配。 此外，这些技术描述了如何以相对精细的粒度来执行重新分配，避免了需要在所有节点上执行大量数据的批量重新分配，仅仅重新分配其中一个节点上的几个数据项的所有权。

公开(公告)号：US20040221116A1

公开(公告)日：2004-11-04

申请号：US10426471

申请日：2003-04-29

Applicant: Oracle International Corporation

Inventor： Wei Ming Hu ,  Juan R. Loaiza ,  Roger J. Bamford ,  Vikram Joshi ,  Arvind Nithrakashyap ,  Tudor Bosman ,  Vinay Srihari ,  Alok Pareek

IPC: G06F012/00

CPC classification number: G06F17/30595 ,  Y10S707/99953

Abstract: 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. At recovery, ordering and/or merging of redo records may occur to satisfy database consistency requirements.

公开(公告)号：US20040215883A1

公开(公告)日：2004-10-28

申请号：US10831248

申请日：2004-04-23

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Roger J. Bamford ,  Sashikanth Chandrasekaran ,  Angelo Pruscino

IPC: G06F012/08

CPC classification number: G06F17/3048 ,  G06F12/0871 ,  G06F12/0893 ,  Y10S707/99952

Abstract: Various techniques are described for improving the performance of a multiple node system by allocating, in two or more nodes of the system, partitions of a shared cache. A mapping is established between the data items managed by the system, and the various partitions of the shared cache. When a node requires a data item, the node first determines which partition of the shared cache corresponds to the required data item. If the data item does not currently reside in the corresponding partition, the data item is loaded into the corresponding partition even if the partition does not reside on the same node that requires the data item. The node then reads the data item from the corresponding partition of the shared cache.

Abstract translation: 描述了各种技术，用于通过在系统的两个或更多个节点中分配共享高速缓存的分区来提高多节点系统的性能。 在系统管理的数据项和共享缓存的各个分区之间建立映射。 当节点需要数据项时，节点首先确定共享缓存的哪个分区对应于所需的数据项。 如果数据项当前不在相应的分区中，则即使分区不在需要数据项的同一节点上，数据项也会被加载到相应的分区中。 然后，节点从共享高速缓存的相应分区读取数据项。

公开(公告)号：US20040215640A1

公开(公告)日：2004-10-28

申请号：US10831413

申请日：2004-04-23

Applicant: ORACLE INTERNATIONAL CORPORATION

Inventor： Roger J. Bamford ,  Sashikanth Chandrasekaran ,  Angelo Pruscino

IPC: G06F007/00

CPC classification number: G06F17/30575

Abstract: Various techniques are described for improving the performance of a shared-nothing database system in which at least two of the nodes that are running the shared-nothing database system have shared access to a disk. Specifically, techniques are provided for recovering the data owned by a failed node using multiple recovery nodes operating in parallel. The data owned by a failed node is reassigned to recovery nodes that have access to the shared disk on which the data resides. The recovery logs of the failed node are read by the recovery nodes, or by a coordinator process that distributes the recovery tasks to the recovery nodes.

Abstract translation: 描述了用于改善无共享数据库系统的性能的各种技术，其中运行无共享数据库系统的至少两个节点具有对盘的共享访问。 具体地，提供了用于使用并行操作的多个恢复节点来恢复由故障节点拥有的数据的技术。 由故障节点拥有的数据重新分配给可访问数据所在的共享磁盘的恢复节点。 故障节点的恢复日志由恢复节点或由将恢复任务分发到恢复节点的协调进程读取。