International Business Machines Corporation

Thomas James Freund

Robert Anthony Storey

Glyn Normington

James Thomas Rayfield

Avraham Leff

Donald Francis Ferguson

Stephen James Cocks

Iain Stuart Houston

Andrew John Bainbridge

Stanley Alan Smith

Simon Antony Holdsworth

Iain Stuart Caldwell Houston

Simon Anthony Holdsworth

R Anthony Storey

Gordon Douglas Hutchison

Ian J Mitchell

Robert Howard High, Jr

Steven Powell

Larry K Loucks

Martin Mulholland

Kathryn Sarah Warr

Andrew Simon Clement

Peter John Schommer

Edward Ellis Cobb

Charlie James Redlin

Ann Eleanor Dalton

Barry Dickinson

Robert L Wierwille

Jonathan Peter Hoare Lawrence

Chij-Mehn Chang

In a workload managed system comprising a plurality of server processes each capable of supporting a given program entity, such as an Enterprise JavaBeans&#x2122; specified stateful session bean, a stateful session bean instance is passivated, by writing it to a bean store, on completion of a unit of work. On next use the session bean is reactivated, by reading it from the bean store, in any one of the plurality of servers thereby allowing workload management for stateful session beans. A routing table is maintained, in non-volatile mass storage, that contains location information for units of work and stateful session bean instances, used to maintain unit of work-server affinity for the lifetime of the unit of work Stateful session beans instances are associated with ID keys that include a flag that is used to indicate whether or not the routing table contains location information for the bean instance.

Workload management of stateful program entities

The present invention provides a more flexible version of an EJB container which permits easy definition an EJB component which observes a behavior pattern which is not typical of a session, entity or message driven bean types. In this flexible EJB container, behavior characteristics normally fixed by the bean type of the EJB component, such as passivation policy, usage, recoverability, and relocatability can be separately defined for each EJB component.

Enterprise javabeans container

An apparatus for scheduling and dispatching client requests for execution by a server object in a heterogeneous object-oriented client/server computing environment, the apparatus comprising: a request-holding buffer having an input connected to a communications channel which channels the client requests to the apparatus, and an output; a plurality of parallel execution threads connected to the output of the buffer; and a scheduling means for distributing client requests stored in the buffer to the plurality of execution threads, characterized in that: the scheduling means places client requests held in the buffer in priority order based on a priority determining rule which takes into account the state of the plurality of execution threads and the nature of each of the held requests.

Apparatus and method for scheduling and dispatching queued client requests within a server in a client/server computer system

An apparatus for dispatching client requests for execution by a server object in a heterogeneous object-oriented client/server computing environment, the apparatus has: a request-holding buffer having an input connected to a communications channel which channels the client requests to the apparatus, and an output; a plurality of parallel execution threads connected to the output of the buffer; and a semantic concurrency control means for examining the semantics of a request in the buffer and the semantics of each request presently being executed on any of the plurality of parallel execution threads, and for delaying the request from being dispatched from the buffer to an execution thread if the examined semantics of the requests indicate that such dispatch would cause conflicting access to the server object's resources.

Apparatus and method for performing semantic concurrency control in dispatching client requests within a server in a client/server computer system

In a data processing environment where a client requests a server to perform part of its processing, a method of updating the client's version of server-related data without requiring the client to be a server, includes steps of: receiving, at a control point server, a first request from the client requesting that server-related data be transferred from the control point server to the client; and in response to the first request, sending the server-related data from the control point server to the client, along with a unique bind token identifying a version number of the server-related data such that each time the server-related data changes a new unique bind token is associated with the data, where the client uses the server-related data to form a second request for the server to perform part of the client's processing, and where the client sends said bind token to the server as part of the second request.

Updating server-related data at a client

A system and method for using the TRAN procedural transaction coordinator, from the Encina product produced by Transarc Corporation, as the core of an OMG-compliant Object Transaction Service. The method allows the object-oriented Object Transaction Service to interoperate with Encina procedural applications. The interoperation involves coordinated processing of both object oriented transactional requests and Encina procedural transactional requests. Both object oriented and procedural requests can be part of a single atomic transaction without requiring gateways between the products. A system of implementation classes are used to transform object-oriented method invocations into the necessary procedural calls. The implementation classes also accept upcalls from the procedural TRAN and transform them into the necessary Object Transaction Service method invocations.

System and method for creating an object oriented transaction service

A method of performing workload management within an object-oriented client/server computing environment wherein one of a plurality of servers is chosen to satisfy a client request based on at least one workload management policy, said method, which takes place within the client, includes steps of: deciding whether a client application program has issued a request for a server to do some work; forming an extended object reference based on said request, said extended object reference having, in addition to a server address field and an object key field, at least one additional field; accessing workload management policy data based on said extended object reference; and selecting one of said plurality of servers based on said accessed workload management policy data.

Workload management in a client-server network with distributed objects

A system and process for enhancing procedural software using object oriented classes. Implementation classes are constructed that provide a defined object oriented interface to applications and are able to invoke the procedural software using defined procedural application program interfaces (APIs). New function is added to the software by adding classes that interface to the implementation classes or directly to the procedural API. The new function builds upon the procedural software without accessing the procedural software source code or modifying that source code.

System and method for functionally enhancing procedural software using

An apparatus for dispatching client requests within a server computer system, wherein the client requests are issued from at least one client computer system on a different platform from said server computer system and are passed through a communications channel to said server computer system, the apparatus comprising: a buffer having an input connected to said communications channel and an output; a plurality of parallel execution threads connected to said output of said buffer; and a scheduling means for distributing client requests stored in said buffer to said plurality of execution threads in a manner such that related client requests are sent to the same execution thread.

Apparatus and method for dispatching client method calls within a server

A method and system for implementing a Restart Service for the Object Transaction Service are described. The present invention provides a method and system which trigger restart of an OTS instance upon system recovery or upon system failure. The Restart Service runs independently of the client or server processes which it restarts. When a client or server enters a pending state for a transaction, a permanent record containing information to allow the OTS instance to be restarted is stored in a Restart Repository. In the event of system recovery being needed, or of a system failure, a Restart Daemon reads information from the Restart Repository and recreates the process context. The Recovery Service is initialized and log data replayed to a Transaction Manager to determine the outcome of pending transactions. Failed objects and instances of the OTS are restarted.

Restart and recovery of OMG-compliant transaction systems

In brief, an object oriented thread context manager, a method and computer program product are provided for object oriented thread context management, particularly for relational databases working with distributed transactions. A context manager is provided for managing a plurality of ContextControl objects. Each ContextControl object comprises a plurality of methods for creating, resuming and suspending context on a thread for a target object. A ContextCoordinator class is provided for managing calls to the plurality of ContextControl objects. A ContextHandleList is provided for storing context information for the ContextControl objects. A specialized ContextCoordinator is provided for managing calls to a specialized ones of the ContextControl objects. A DatabaseContextCoordinator is an example of the specialized ContextCoordinator. The specialized ones of the ContextControl objects are registered and unregistered with the ContextCoordinator class and then registered DatabaseContextCoordinator.

Thread context manager for relational databases, method and computer

The invention provides a mechanism to integrate differing transaction protocols by augmenting an existing Resource Manager to act as both a Transaction Manager and a Resource Manager within a system which also contains a standards-based Transaction Manager which has overall transaction management responsibility. The Transaction Manager within the Resource Manager acts as an interface to provide specific mappings between the Transaction Manager which has overall transaction management responsibility and a proprietary transaction processing system which it manages. The interface is required to map different transaction identification specifications, record appropriate state information and have procedures to effect failure and restart scenarios.

Heterogeneous operations with differing transaction protocols

The invention allows the participation of a resource manager in a transaction which is coordinated by a transaction manager with which the resource manager's protocols are not compatible. More particularly, a mapper records a connection reference which the application program obtains from the resource manager and a transaction reference which the application program obtains from the transaction manager. The resource manager stores recovery information in an associated log file.

Operating a transaction manager with a non-compliant resource manager

A system for, and method of, providing an interface to an application program for accessing networking functions. The application program interface translates routines requesting networking functions to the operating system commands which contain facilities for accessing networking functions. In addition, the application program interface externalizes the operating system commands for use by the application program in accessing networking functions.

Growing community of inventors

Winchester, United Kingdom

Thomas James Freund