Abstract: The amount of memory being utilized to store token state information is monitored. In response to the monitoring, one or more actions are taken. For instance, if the monitoring indicates that too much memory is being used to store token state information, then one or more actions are performed to reclaim memory and/or obtain additional memory elsewhere. These actions may include informing one or more clients to reduce their cache sizes, thereby relinquishing tokens; reducing or eliminating one or more byte range token trees; and/or migrating the token server from one node to another node. If the monitoring indicates that additional memory can be used for storing token state information, then one or more client nodes are informed that their cache sizes can be increased.

Abstract: A method is provided for limiting access to disks and files in the event of a system partitioning occurring as the result of a node failure in a data distributed processing system in which files are shared amongst a plurality of independently running nodes. The nodes in the system are provided with limited duration leases which permit data access and which have to be periodically renewed. Each partition is also associated with a quorum which is also a necessary element in providing access at proper times. The lease and quorum concepts work together to insure that recovery operations do not occur until recovery is possible. The lease concept thus is also seen as further operating in close cooperation with the quorum concept to prevent long delays in the recovery process that could otherwise occur.

Abstract: The determination of node and/or adapter liveness in a distributed network data processing system is carried out via one messaging protocol that can be assisted by a second messaging protocol which is significantly less susceptible to delay, especially memory blocking delays encountered by daemons running on other nodes. The switching of protocols is accompanied by controlled grace periods for needed responses. This messaging protocol flexibility is also adapted for use as a mechanism for controlling the deliberate activities of node addition (birth) and node deletion (death).

Abstract: A computer system having a shared disk file system running on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. A metadata node manages file metadata for parallel read and write actions. Metadata tokens are used for controlled access to the metadata and initial selection and changing of the metadata node.

Abstract: A computer system having a shared disk file system running on on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Methods are provided for use as a parallel file system in a shared disk environment by use of a scalable directory service for the system with a stable cursor, a segmented allocation map. Dynamic prefetch and cached balance pools for multiple accesses improve the system. Extended file attributes are used for implementation of Access Control Lists in a parallel file system. Improvements to caching and cache performance developments balance pools for multiple accesses. A metadata node manages file metadata for parallel read and write actions.

Abstract: A computer system having a shared disk file system running on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Locking techniques reduce the overhead of a token manager which is also used in the file system recovery if a computer participating in the management of shared disks becomes unavailable or failed. Synchronous and asynchronous takeover of a metadata node occurs for correction of metadata which was under modification and a new computer node to be a metadata node for that file. Locks are not constantly required to allocate new blocks on behalf of a user.

Abstract: A computer system having a shared disk file system running on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Access to a file by a processor node is controlled by tokens transferred to the node from a token manager. To prevent another processor node from removing a token after the token has been received, but before it performs the operation on the file, each process can lock the token after it has been received. A node with a token can lock a byte range of a file, which byte range may include all or only some of byte range cornered by the token.

Abstract: A computer system having a shared disk file system running on on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Methods are provided for use as a parallel file system in a shared disk environment by use of a scalable directory, service for the system with a stable cursor, a segmented allocation map. Dynamic prefetch and cached balance pools for multiple accesses improve the system. Extended file attributes are used for implementation of Access Control Lists in a parallel file system, improvements to caching and cache performance developments balance pools for multiple accesses. A metadata node manages file metadata for parallel read and write actions.

Abstract: A computer system having a shared disk file system running on multiple computers each having their own instance of an operating system and being coupled for parallel data disks. One of the computers serves as a metadata node and manages metadata for parallel read and write actions for a particular file. Metadata is transferred from and to this file from the other computers via this medadata node computer.

Abstract: A computer system having a shared disk file system running on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Methods are provided for use as a parallel file system in a shared disk environment by use of a scalable directory service for the system with a stable cursor, and a segmented allocation map. Dynamic prefetch and cached balance pools for multiple accesses improve the system. Extended file attributes are used for implementation of Access Control Lists in a parallel file system. Improvements to caching and cache performance developments balance pools for multiple accesses. A metadata node manages file metadata for parallel read and write actions.

Abstract: A computer system having a shared disk file system running on on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Methods are provided for use as a parallel file system in a shared disk environment by use of a scalable directory service for the system with a stable cursor, a segmented allocation map. Dynamic prefetch and cached balance pools for multiple accesses improve the system. Extended file attributes are used for implementation of Access Control Lists in a parallel file system. Improvement to caching and cache performance development balance pools for multiple accesses. A metadata node manages file metadata for parallel read and write actions.

Abstract: A computer system having a shared disk file system running on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Methods are provided for use as a parallel file system in a shared disk environment by use of a scaleable directory service for the system with a stable cursor, and a segmented allocation map. Dynamic prefetch and cached balance pools for multiple accesses improve the system. Extended file attributes are used for implementation of Access Control Lists in a parallel file system. A metadata node manages file metadata for parallel read and write actions. For our system, tokens are used for metadata node selection and identification. We have provided recoverable local shares for quota Management.

Abstract: A computer system having a shared disk file system running on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Methods are provided for use as a parallel file system in a shared disk environment by use of a scalable directory service for the system with a stable cursor, a segmented allocation map. Dynamic prefetch and cached balance pools for multiple accesses improve the system. Extended file attributes are used for implementation of Access Control Lists in a parallel file system. Improvements to caching and cache performance developments balance pools for multiple accesses. A metadata node manages file metadata for parallel read and write actions.

Abstract: A computer system having a shared disk file system running on on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Methods are provided for use as a parallel file system in a shared disk environment by use of a scalable directory service for the system with a stable cursor, a segmented allocation map. Synchronous and asynchronous takeover of a metadata node occurs for correction of metadata which was under modification and a new computer node to be a metadata node for that file. Locks are not constantly required to allocate new blocks on behalf of a user. We have provided recoverable local shares for Quota Management. A quota server and a quota client are provided for each file system, and a quotacheck utility allows parallel environments with minimal interference to other applications which require the use of quotas.

Abstract: A computer system having a shared disk file system running on on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Methods are provided for use as a parallel file system in a shared disk environment by use of a scalable directory service for the system with a stable cursor, a segmented allocation map. Dynamic prefetch and cached balance pools for multiple accesses improve the system. Extended file attributes are used for implementation of Access Control Lists in a parallel file system. Improvements to caching and cache performance developments balance pools for multiple accesses. A metadata node manages file metadata for parallel read and write actions.

Abstract: A computer system having a shared disk file system running on on multiple computers each having their own instance of an operating system and being coupled for parallel data sharing access to files residing on network attached shared disks. Method are provided for use as a parallel file system in a shared disk environment by use of scalable directory service for the system with a stable cursor, a segmented allocation map. Dynamic prefetch and cached balance pools for multiple accesses improve the system. Extended file attributes are used for implementation of Access Control Lists in a parallel file system. Improvements to caching and cache performance developments balance pools for multiple accesses. A metadata node manages file metadata for parallel read and write actions.

Abstract: A computer system having a shared parallel disk file system running on a network for multiple computers each having their own instance of an operating system and with a protocol that makes disks appear to be locally attached to each file system. This parallel file system in a shared disk environment uses scalable directory service method improvements to caching and cache performance developments balance pools for multiple accesses. A metadata node manages file metadata, and locking techniques reduce the overhead of a token manager which is also used in the file system recovery if a computer participating in the management of shared disks becomes unavailable or failed. Synchronous and asynchronous takeover of a metadata node occurs for correction of metadata which was under modification and a new computer node to be a metadata node for that file. Locks are not constantly required to allocate new blocks on behalf of a user.

Abstract: A method and apparatus are provided for integrating application programs and objects of the application programs in an integrated graphical user interface processing environment, such as a windows environment. The method and apparatus facilitate the integration without requiring modifications of the application program software, and without requiring that the application programs conform to any particular communication protocol. When a command input, such as a mouse click by a user in a windows environment, indicates that an object from one application is to be dropped onto a window in which another application is running, the properties of the window and the attributes of the object are used to search a rule database to identify a rule which is applicable to these particular types of object and application. The rule contains an action clause, which specifies various actions which are to be executed automatically, to invoke a desired operation by or related to the application program on the object.