International Business Machines Corporation

Kenneth C Briskey

Marcos Nogueira Novaes

Larry Bert Brenner

Krystal Kay Rothaupt

Richard C Russell

Stephanie A Beals

Gregory D Laib

Rosario A Uceda-Sosa

Bruce M Potter

Kesavaprasath Ranganathan

The management and use of replicated distributed transactions is facilitated. A distributed synchronous transaction system protocol is provided to manage the replication of distributed transactions for client application instances. The distributed synchronous transaction system allows transactions to be replicated without having the client application instances be aware of other instances to receive the transaction. Further, if a failure occurs during processing of a distributed replicated transaction, the distributed synchronous transaction system manages the recovery of the failure.

Method, system and program products for managing processing groups of a distributed computing environment

A common interface (API) is provided which permits a single diagnostic probe manager to communicate with and to control a plurality of diagnostic probes. Through this interface the diagnostic probes are enabled to pass information concerning dependencies between software levels present in a hierarchical stack. This information is particularly useful in that it permits the probe manager to direct diagnostic efforts at the lowest desirable level so as to avoid the problems that occur when problems are indicated at a high level but which are actually caused by lower level software components.

Diagnostic probe management in data processing systems

Dynamic reconfiguration of a quorum group of processors and recovery procedure therefore are provided for a shared nothing distributed computing system. Dynamic reconfiguration proceeds notwithstanding unavailability of at least one processor of the quorum group of processors assuming that a quorum of the remaining processors exists. Recovery processing is implementing by the group of processors so that the at least one processor which was unavailable during the dynamic reconfiguration of the group is able to obtain current state information once becoming active. Each processor of the group of processors includes an incarnation number and a list of member processors which participated in a commit process resulting in its incarnation number. The recovery processing includes exchanging the processors' incarnation numbers and lists of processors for propagation of the current state of the quorum group of processors to the at least one processor now becoming available. Determination of a relaxed quorum number for a quorum based operation of a distributed computing system is also described.

Relaxed quorum determination for a quorum based operation

Relaxed quorum determination for a quorum based operation of a distributed computing system

Dynamic reconfiguration of a quorum group of processors in a distributed computing system

Dynamic reconfiguration of a quorum group of processors and recovery procedure therefore are provided for a shared nothing distributed computing system. Dynamic reconfiguration proceeds notwithstanding unavailability of at least one processor of the quorum group of processors assuming that a quorum of the remaining processors exists. Recovery processing is implementing by the group of processors so that the at least one processor which was unavailable during the dynamic reconfiguration of the group is able to obtain current state information once becoming active. Each processor of the group of processors includes an incarnation number and a list of member processors which resulted from a commit process resulting in its incarnation number. The recovery processing includes exchanging the processors' incarnation numbers and lists of processors for propagation of the current state of the quorum group of processors to the at least one processor now becoming available.

Recovery procedure for a dynamically reconfigured quorum group of processors in a distributed computing system

A parallel distributed computing system having a plurality of processors connected in a network of nodes, each node having software installed thereon, and a control workstation controlling the nodes in the network. A list of the levels of the software installed at each node is stored at the control workstation. A list of software subsystems affected by a command to be executed is stored at the nodes of the network, including the control workstation. In addition, a control script for each of said software subsystems is stored at the nodes, including the control workstation. Each control script provides a routine to be followed for the associated subsystem on the associated node or control workstation during the execution of the command. Since the control scripts are compatible with the level of software installed on the target node, the command will be performed such as to be compatible with the software installed on the target node.

Managing multiple versions of multiple subsystems in a distributed

A method for use in a parallel distributed computing system having a plurality of processors connected in a network of nodes, each node having software installed thereon, and a control workstation controlling the nodes in the network. A list of the levels of the software installed at each node is stored at the control workstation. A list of software subsystems affected by a command to be executed is stored at the nodes of the network, including the control workstation. In addition, a control script for each of said software subsystems is stored at the nodes, including the control workstation. Each control script provides a routine to be followed for the associated subsystem on the associated node or control workstation during the execution of the command. Since the control scripts are compatible with the level of software installed on the target node, the command will be performed such as to be compatible with the software installed on the target node.

Method for managing multiple versions of multiple subsystems in a

In accordance with a preferred embodiment of the present invention, a method and an apparatus is disclosed for providing a corresponding view of a partitioned distributed parallel processing environment. The parallel processing system itself is comprised of a plurality of nodes connected to one another and to a central control element via a network. The central control element is used for communication and status maintenance of the system environment. The apparatus and method provides for separate storing of system data pertaining to different sub-environments in a system data repository located in the central control element. Each data pertaining exclusively to a sub-environment is identified as such and limited access to that data is provided only to the nodes residing in that environment. A system view is constructed based on the data in this repository. Once a view is constructed, the view is identified and stored separately as belonging to a specific sub-environment. A client, or a querying node, is then provided access to its sub-environment's view through the central control element.

Apparatus and a method for creating isolated sub-environments using host

A method of deciphering all communications for a given sub-environment in a partitioned parallel processing environment is suggested through the use of daemons. The parallel processing environment is a UNIX based operating environment comprising of a plurality of nodes connected through a network to one another and to a central control element used for controlling all communications. The parallel processing environment initially operates as a single computing unit, which is later partitioned into two or more isolated sub-environments. The method comprises of storing all system data in a repository provided in the central control element, each data being organized as belonging exclusively to one sub-environment, or globally to all sub-environments. The central control element is then apportioned, so that the data belonging exclusively to one sub-environment is located at a given address, each sub-environment being assigned a different address. A dedicated daemon is then started in the central control element for each sub-environment. The daemon is provided its respective sub-environment's address in the central control element. The daemon 'listens' in and deciphers all communications, only returning back those communication pertaining to its sub-environments back to the nodes of its respective sub-environment.

Use of daemons in a partitioned massively parallel processing system

In accordance with a preferred embodiment of the present invention, an application and method of preserving persistent logical partitions, is suggested for use in a partitioned massively parallel processing system environment. All system data, including configuration data is stored in a central control element in a special configuration object class file. The configuration object class file maps the resources to different sub-environments. Upon a system shut-down or re-booting of any resource, the configuration information stored in the central control element is recovered to re-establish the sub-environments integrity.

System for preserving logical partitions of distributed parallel

In accordance with a preferred embodiment of the present invention, a method and apparatus is disclosed for partitioning a massively distributed parallel processor into at least two isolated sub-environments. The parallel processing environment is comprised of a plurality of nodes connected to one another via a network in such a way as to form a single system unit initially. A central control element is provided for controlling and maintaining all communications and status information between nodes. The nodes and the central control element are in processing communication with one another via the network. All system data is deposited in a system data repository located in the central control element. Once the environment is partitioned, the system data stored in this repository is organized into system or partitioned classes, with the partitioned classes only being accessible selectively to nodes residing in one environment or another.

Growing community of inventors

Hyde Park, NY, United States of America

Kenneth C Briskey