公开(公告)号：US08850007B2

公开(公告)日：2014-09-30

申请号：US13156315

申请日：2011-06-08

申请人： Michael T. Massa ,  David A. Dion ,  Rajsekhar Das ,  Rushabh A. Doshi ,  David B. Lomet ,  Gor N. Nishanov ,  Philip A. Bernstein ,  Rod N. Gamache ,  Rohit Jain ,  Sunita Shrivastava

发明人： Michael T. Massa ,  David A. Dion ,  Rajsekhar Das ,  Rushabh A. Doshi ,  David B. Lomet ,  Gor N. Nishanov ,  Philip A. Bernstein ,  Rod N. Gamache ,  Rohit Jain ,  Sunita Shrivastava

IPC分类号： G06F15/173 ,  G06F11/08 ,  G06F11/18 ,  G06F11/14 ,  G06F11/20 ,  G06F17/30 ,  G06F11/16

CPC分类号： G06F17/30575 ,  G06F11/1425 ,  G06F11/1471 ,  G06F11/1479 ,  G06F11/1482 ,  G06F11/1662 ,  G06F11/181 ,  G06F11/182 ,  G06F11/2023 ,  G06F11/2035 ,  G06F11/2058 ,  G06F2201/82

摘要： A method and system for increasing server cluster availability by requiring at a minimum only one node and a quorum replica set of replica members to form and operate a cluster. Replica members maintain cluster operational data. A cluster operates when one node possesses a majority of replica members, which ensures that any new or surviving cluster includes consistent cluster operational data via at least one replica member from the immediately prior cluster. Arbitration provides exclusive ownership by one node of the replica members, including at cluster formation, and when the owning node fails. Arbitration uses a fast mutual exclusion algorithm and a reservation mechanism to challenge for and defend the exclusive reservation of each member. A quorum replica set algorithm brings members online and offline with data consistency, including updating unreconciled replica members, and ensures consistent read and update operations.

摘要翻译： 通过至少要求一个节点和副本成员的仲裁复制集来形成和操作集群，来提高服务器集群可用性的方法和系统。 副本成员维护集群操作数据。 当一个节点拥有大多数副本成员时，集群就会运行，从而确保任何新的或存活的集群通过至少一个来自紧接在前的集群的副本成员包括一致的集群操作数据。 仲裁提供复制成员的一个节点的独占所有权，包括在集群形成时以及所有节点出现故障时。 仲裁使用快速互斥算法和保留机制来挑战和保护每个成员的独家保留。 仲裁复制集算法使成员在线和离线具有数据一致性，包括更新未协调的副本成员，并确保一致的读取和更新操作。

公开(公告)号：US20130339533A1

公开(公告)日：2013-12-19

申请号：US13527384

申请日：2012-06-19

申请人： Matthew A. Neerincx ,  Luiz F. Santos ,  Oleg Ignat ,  David B. Lomet ,  Quetzalcoatl Bradley ,  Raghu Ram ,  Chadwin J. Mumford ,  Peter Gvozdjak ,  Balendran Mugundan

发明人： Matthew A. Neerincx ,  Luiz F. Santos ,  Oleg Ignat ,  David B. Lomet ,  Quetzalcoatl Bradley ,  Raghu Ram ,  Chadwin J. Mumford ,  Peter Gvozdjak ,  Balendran Mugundan

IPC分类号： G06F15/16 ,  G06F17/30

CPC分类号： G06F17/30566 ,  G06F11/2023 ,  G06F11/2097 ,  H04L67/142 ,  H04L67/146 ,  H04L67/148 ,  H04L69/40

摘要： Systems and methods are described that establish and maintain a virtual session between a client and one or more database servers. A database server establishes a first session with a client wherein establishing the virtual session with the client comprises associating a virtual session identifier (ID) with the first session, generates state information in association with the first session, and stores the state information in a repository in association with the virtual session ID. After the first session fails, a same or different database server establishes a second session with the client wherein establishing the second session with the client comprises receiving the virtual session ID from the client, accesses the state information that was stored in the repository in association with the virtual session ID, and associates the state information with the second session.

摘要翻译： 描述了在客户端和一个或多个数据库服务器之间建立和维护虚拟会话的系统和方法。 数据库服务器与客户端建立第一会话，其中与客户端建立虚拟会话包括将虚拟会话标识符（ID）与第一会话相关联，生成与第一会话关联的状态信息，并将状态信息存储在存储库 与虚拟会话ID相关联。 在第一次会话失败之后，相同或不同的数据库服务器与客户端建立第二个会话，其中与客户端建立第二个会话包括从客户端接收虚拟会话ID，与存储在存储库中的状态信息相关联地访问 虚拟会话ID，并将状态信息与第二会话相关联。

公开(公告)号：US20110302143A1

公开(公告)日：2011-12-08

申请号：US12791898

申请日：2010-06-02

申请人： David B. Lomet

发明人： David B. Lomet

IPC分类号： G06F17/30

CPC分类号： G06F16/2322

摘要： Multiple versions of a set of data objects can be maintained to allow concurrent conflicting access to the objects. Additionally, a range of acceptable timestamps for each transaction in a set of database transactions can be tracked. Conflicting access requests for an object in the set of objects can be detected, and the requests can be made by two or more conflicting transactions in the set of transactions. A range of acceptable timestamps for at least one of the conflicting transactions can be adjusted, such that an order of transaction timestamps can be maintained in accordance with a specified transaction isolation level. Such timestamp range adjustment can frequently permit conflicting read and write accesses to proceed concurrently. When concurrent access cannot be allowed while maintaining such an order of transaction timestamps, in many cases one of the conflicting accesses can be blocked instead of aborting one of the transactions.

摘要翻译： 可以维护一组数据对象的多个版本，以允许对对象的并发冲突访问。 另外，可以跟踪一组数据库事务中的每个事务的可接受的时间戳范围。 可以检测到对象集中的对象的访问请求冲突，并且可以通过事务集中的两个或多个冲突事务来进行请求。 可以调整至少一个冲突事务的可接受的时间戳的范围，使得可以根据指定的事务隔离级别来维护事务时间戳的顺序。 这种时间戳范围调整可以经常允许冲突的读和写访问同时进行。 当维护这种交易时间戳的顺序时，不能允许并发访问，在许多情况下，可以阻止一个冲突访问，而不是中止其中一个事务。

公开(公告)号：US20090182783A1

公开(公告)日：2009-07-16

申请号：US12013389

申请日：2008-01-11

申请人： David B. Lomet

发明人： David B. Lomet

IPC分类号： G06F17/30

CPC分类号： G06F17/30353

摘要： Systems and methods for facilitating more efficient timestamping in a lazy timestamping transaction time database environment are described herein. A recovery log component can store timestamp information of a transaction in a commit record of the transaction, wherein the commit record of the transaction is included in a recovery log. A volatile reference count component can update reference count data of the transaction in a volatile timestamp table to reflect a number of records of the transaction that do not persistently include timestamp information. Further, a checkpoint component can update timestamp information for a batch of transactions, wherein the timestamp information is updated in a record of the persistent timestamp table to ensure that the timestamp information persists in the record of the persistent timestamp table before the commit record of the transaction that contains the transaction's timestamp information is deleted from the recovery log.

摘要翻译： 在这里描述了用于在延迟的时间戳交易时间数据库环境中促进更有效的时间戳的系统和方法。 恢复日志组件可以将事务的时间戳信息存储在事务的提交记录中，其中事务的提交记录被包括在恢复日志中。 易失性引用计数组件可以在易失性时间戳表中更新事务的引用计数数据，以反映不持续地包含时间戳信息的事务的记录数。 此外，检查点组件可以更新一批事务的时间戳信息，其中在永久时间戳表的记录中更新时间戳信息，以确保时间戳信息在持续时间戳表的记录之前保持在 从恢复日志中删除包含事务的时间戳信息的事务。

公开(公告)号：US07509351B2

公开(公告)日：2009-03-24

申请号：US11246488

申请日：2005-10-07

申请人： David B. Lomet ,  Mark R. Tuttle

发明人： David B. Lomet ,  Mark R. Tuttle

IPC分类号： G06F17/30

CPC分类号： G06F11/1471 ,  G06F2201/80 ,  G06F2201/82 ,  Y10S707/99933 ,  Y10S707/99942 ,  Y10S707/99944 ,  Y10S707/99952 ,  Y10S707/99953

摘要： Logical logging to extend recovery is described. In one aspect, a dependency cycle between at least two objects is detected. The dependency cycle indicates that the two objects should be flushed simultaneously from a volatile main memory to a non-volatile memory to preserve those objects in the event of a system crash. One of the two objects is written to a stable of to break the dependency cycle. The other of the two objects is flushed to the non-volatile memory. The object that has been written to the stable log is then flushed to the stable log to the non-volatile memory.

摘要翻译： 描述了扩展恢复的逻辑记录。 在一个方面，检测至少两个对象之间的依赖关系。 依赖关系周期表示两个对象应该从易失性主存储器同时刷新到非易失性存储器，以在系统崩溃的情况下保留这些对象。 两个对象之一被写入一个稳定的破坏依赖关系周期。 两个对象中的另一个被刷新到非易失性存储器。 已将写入稳定日志的对象刷新到稳定日志到非易失性存储器。

公开(公告)号：US07430559B2

公开(公告)日：2008-09-30

申请号：US11232397

申请日：2005-09-21

申请人： David B. Lomet

发明人： David B. Lomet

IPC分类号： G06F17/00

CPC分类号： G06F17/30864 ,  Y10S707/99942 ,  Y10S707/99943 ,  Y10S707/99944 ,  Y10S707/99945

摘要： A system and methodology that facilitate persistence for an execution state is provided. The system and methodology employ generalized “idempotent” request(s) that have the property they only execute a request once, and always return the result of that first execution should the request be repeated so as to ensure exactly once execution. A calling middle tier component can exploit these procedures so that it can engage in exploratory reads (which are not idempotent) yet still be able to have their state recovered via replay based on the log at the client and the results retained by the generalized idempotent procedures provided by back end services. The system and methodology can be employed to facilitate successful replay of logless persistent component(s), (e.g., components that do not themselves log any information).To exploit generalized idempotent procedures, what a middle tier logless component can do with the results of non-idempotent exploratory reads must be circumscribed so that these results only impact arguments to the next generalized idempotent procedure invoked from the middle tier.Optionally, the system and methodology can facilitate idempotent procedure(s) which support idempotent request abort(s). When an idempotent request abort is requested, it can be identified with the request via a request identifier. Then subsequent request(s) with the same request identifier can return with the same “abort” message.

摘要翻译： 提供了一种促进执行状态的持久性的系统和方法。 系统和方法使用具有它们只执行一次请求的属性的广义的“幂等”请求，并且如果重复该请求，则总是返回该第一次执行的结果，以便确保一次执行。 一个调用的中间层组件可以利用这些过程，以便它可以进行探索性读取（不是幂等），但是仍然可以根据客户端的日志通过重播来恢复其状态，并且通过广义幂等程序保留结果 由后端服务提供。 可以采用该系统和方法来促成无声持久性组件的成功重播（例如，自身不记录任何信息的组件）。 为了利用广义幂等程序，中间层无逻辑组件可以使用非幂等探查性读取的结果进行限制，因此这些结果只会影响从中间层调用的下一个广义幂等过程的参数。 可选地，系统和方法可以促进支持幂等请求中止的幂等过程。 当请求中止等待请求时，可以通过请求标识符与请求一起识别。 然后具有相同请求标识符的后续请求可以返回相同的“中止”消息。

公开(公告)号：US07093162B2

公开(公告)日：2006-08-15

申请号：US10879324

申请日：2004-06-29

申请人： Roger S. Barga ,  David B. Lomet

发明人： Roger S. Barga ,  David B. Lomet

IPC分类号： G06F11/00

CPC分类号： G06F11/1482 ,  G06F11/1438 ,  G06F11/1471

摘要： Persistent components are provided across both process and server failures, without the application programmer needing take actions for component recoverability. Application interactions with a stateful component are transparently intercepted and stably logged to persistent storage. A “virtual” component isolates an application from component failures, permitting the mapping of a component to an arbitrary “physical” component. Component failures are detected and masked from the application. A virtual component is re-mapped to a new physical component, and the operations required to recreate a component and reinstall state up to the point of the last logged interaction is replayed from the log automatically.

摘要翻译： 在进程和服务器故障之间提供持久组件，而不需要应用程序员采取措施来实现组件可恢复性。 与状态组件的应用程序交互被透明地拦截并稳定地记录到持久存储器中。 “虚拟”组件将应用程序与组件故障隔离，允许将组件映射到任意“物理”组件。 从应用程序检测并屏蔽组件故障。 一个虚拟组件被重新映射到一个新的物理组件，重新创建组件并重新安装状态直到上次记录的交互操作所需的操作将从日志自动重播。

公开(公告)号：US07047441B1

公开(公告)日：2006-05-16

申请号：US09946050

申请日：2001-09-04

申请人： David B. Lomet ,  Roger Barga ,  Gerhard Weikum

发明人： David B. Lomet ,  Roger Barga ,  Gerhard Weikum

IPC分类号： G06F11/00

CPC分类号： G06F11/1471 ,  G06F11/1469 ,  G06F11/1474

摘要： A technique is described for guaranteeing recovery in a computer system comprising of recovery contracts with a plurality of obligations for a message exchange between a first component and a second component. Three forms of contract are described, governing interactions between three types of components. Each contract is bilateral, i.e. between a first component and a second component. The first and second components have mutual agreement on when the contract will be released to facilitate log truncation, and independent and/or autonomous recovery.

公开(公告)号：US5933838A

公开(公告)日：1999-08-03

申请号：US826610

申请日：1997-04-04

申请人： David B. Lomet

发明人： David B. Lomet

IPC分类号： G06F17/00 ,  G06F17/30

CPC分类号： G06F11/1471 ,  G06F2201/80 ,  Y10S707/99938 ,  Y10S707/99953

摘要： This invention concerns a database computer system and method for making applications recoverable from system crashes. The application state (i.e., address space) is treated as a single object which can be atomically flushed in a manner akin to flushing individual pages in database recovery techniques. To enable this monolithic treatment of the application, executions performed by the application are mapped to logical loggable operations which can be posted to the stable log. Any modifications to the application state are accumulated and the application state is periodically flushed to stable storage using an atomic procedure. The application recovery integrates with database recovery, and effectively eliminates or at least substantially reduces the need for check pointing applications. In addition, optimization techniques are described to make the read, write, and recovery phases more efficient.

摘要翻译： 本发明涉及用于使应用从系统崩溃中恢复的数据库计算机系统和方法。 应用状态（即，地址空间）被视为单个对象，其可以类似于在数据库恢复技术中刷新单独页面的方式被原子地刷新。 为了实现对应用程序的这种单一处理，应用程序执行的执行映射到可以发布到稳定日志的逻辑可记录操作。 累积对应用状态的任何修改，并使用原子程序将应用程序状态定期刷新到稳定存储。 应用程序恢复与数据库恢复集成，并有效地消除或至少大大减少了对检查指向应用程序的需求。 此外，描述了优化技术，以使读取，写入和恢复阶段更有效率。

公开(公告)号：US5524205A

公开(公告)日：1996-06-04

申请号：US50747

申请日：1993-04-21

申请人： David B. Lomet ,  Peter M. Spiro ,  Ashok M. Joshi ,  Ananth Raghavan ,  Tirumanjanam K. Rengarajan

发明人： David B. Lomet ,  Peter M. Spiro ,  Ashok M. Joshi ,  Ananth Raghavan ,  Tirumanjanam K. Rengarajan

IPC分类号： G06F12/00 ,  G06F11/14 ,  G06F12/16

CPC分类号： G06F11/1471 ,  G06F2201/87

摘要： Each node in a data processing system contains at least one undo buffer and one least one redo buffer for insuring that any changes made to a section of a non-volatile storage medium, such as a disk, can be removed, if a transaction has not been committed, or can be recreated if the transaction has not been committed. The undo buffers each correspond to a different uncommitted transaction. The redo buffer contains the changes made to a copy of the section which is maintained in the memory.

摘要翻译： 数据处理系统中的每个节点都包含至少一个撤销缓冲区和至少一个重做缓冲区，用于确保如果一个事务没有，就可以删除对非易失性存储介质（如磁盘）的一部分所做的任何更改 已被提交，或者如果事务尚未提交，可以重新创建。 撤销缓冲区各自对应于不同的未提交事务。 重做缓冲区包含对存储器中维护的部分的副本所做的更改。