Abstract: A transaction request is received at a journal-based state management system. The transaction request includes a register processing section indicating an operation to be performed at a journal register allocated to the transaction submitter to store state information of an application. Based on the results of a conflict detection operation performed with respect to the transaction request and on the result of the operation on the journal register, the transaction request is accepted for commit. The value of the journal register is stored at a node of the state management system and provided to the transaction submitter.

Abstract: A data store manager of a multi-data-store journal-based database performs a sequential analysis of committed transaction entries of a journal. A particular entry includes a directive to determine a value of an attribute of a data object based on a result obtained from a value generator, and does not specify the value of the attribute. The data store manager determines the value using a local version of the value generator, and stores the value in a materialized version of the data object. In response to a programmatic read request, the data store manager provides the materialized version of the data object.

Abstract: A transaction request is received at a journal-based state management system. The transaction request includes a register processing section indicating an operation to be performed at a journal register allocated to the transaction submitter to store state information of an application. Based on the results of a conflict detection operation performed with respect to the transaction request and on the result of the operation on the journal register, the transaction request is accepted for commit. The value of the journal register is stored at a node of the state management system and provided to the transaction submitter.

Abstract: A transaction request is received at a journal-based state management system. The transaction request includes a register processing section indicating an operation to be performed at a journal register allocated to the transaction submitter to store state information of an application. Based on the results of a conflict detection operation performed with respect to the transaction request and on the result of the operation on the journal register, the transaction request is accepted for commit. The value of the journal register is stored at a node of the state management system and provided to the transaction submitter.

Abstract: A sequence of configuration-delta messages from a configuration manager of a replication graph established for replicating state information of an application is received at a particular node of the graph. Representations of the messages are stored in a local configuration change repository. Using the repository, the node identifies neighbor source nodes and destination nodes of the graph. Subsequent to receiving a particular configuration-delta message indicating that a neighbor source node has been removed from the graph, a different source node is identified by the particular node, and a request is sent to the different source node to transmit a set of state transition messages pertaining to the application.

Abstract: Methods and apparatus for a semaphore mechanism in a distributed computing environment are disclosed. A state manager coordinating accesses to objects from distributed clients implements programmatic interfaces for semaphore operations. A client process submits a permit record directed to a semaphore instance protecting a shared resource. The client process receives a representation of permit records associated with the resource. The permit records provide an indication of an order in which permit requests for the resource were processed. The client process uses the permit records to determine whether it has been granted a permit, and if it determines that the permit has been granted, performs operations on the resource.

Abstract: A sequence of configuration-delta messages from a configuration manager of a replication graph established for replicating state information of an application is received at a particular node of the graph. Representations of the messages are stored in a local configuration change repository. Using the repository, the node identifies neighbor source nodes and destination nodes of the graph. Subsequent to receiving a particular configuration-delta message indicating that a neighbor source node has been removed from the graph, a different source node is identified by the particular node, and a request is sent to the different source node to transmit a set of state transition messages pertaining to the application.