摘要:
An apparatus and method retrieves a database record from an in-memory database of a parallel computer system using a non-unique key. The parallel computer system performs a simultaneous search on each node of the computer system using the non-unique key and then utilizes a global combining network to combine the local results from the searches of each node to efficiently and quickly search the entire database.
摘要:
A method and apparatus provide data security on a parallel computer system using virtual private networks. An access setup mechanism sets up access control data in the nodes that describes which virtual networks are protected and what applications have access to the protected private networks. When an application accesses data on a protected virtual network, a network access mechanism determines the data is protected and intercepts the data access. The network access mechanism in the kernel may also execute a rule depending on the kind of access that was attempted to the virtual network. Authorized access to the private networks can be made via a system call to the access control mechanism in the kernel. The access control mechanism enforces policy decisions on which data can be distributed through the system via an access control list or other security policies.
摘要:
An apparatus and method retrieves a database record from an in-memory database of a parallel computer system using a unique key. The parallel computer system performs a simultaneous search on each node of the computer system using the unique key and then utilizes a global combining network to combine the results from the searches of each node to efficiently and quickly search the entire database.
摘要:
An apparatus and method retrieves a database record from an in-memory database of a parallel computer system using a non-unique key. The parallel computer system performs a simultaneous search on each node of the computer system using the non-unique key and then utilizes a global combining network to combine the local results from the searches of each node to efficiently and quickly search the entire database.
摘要:
An apparatus and method retrieves a database record from an in-memory database of a parallel computer system using a unique key. The parallel computer system performs a simultaneous search on each node of the computer system using the unique key and then utilizes a global combining network to combine the results from the searches of each node to efficiently and quickly search the entire database.
摘要:
A method and apparatus provide data security on a parallel computer system using virtual private networks. An access setup mechanism sets up access control data in the nodes that describes which virtual networks are protected and what applications have access to the protected private networks. When an application accesses data on a protected virtual network, a network access mechanism determines the data is protected and intercepts the data access. The network access mechanism in the kernel may also execute a rule depending on the kind of access that was attempted to the virtual network. Authorized access to the private networks can be made via a system call to the access control mechanism in the kernel. The access control mechanism enforces policy decisions on which data can be distributed through the system via an access control list or other security policies.
摘要:
A method and apparatus for transparently handling recurring correctable errors and uncorrectable errors in a mirrored memory system prevents costly system shutdowns for correctable memory errors or system failures from uncorrectable memory errors. When a high number of correctable errors are detected for a given memory location, a memory relocation mechanism in the hypervisor moves the data associated with the memory location to an alternate physical memory location transparently to the partition such that the partition has no knowledge that the physical memory actualizing the memory location has been changed. When a correctable error occurs, the memory relocation mechanism uses data from a partner mirrored memory block as a data source for the memory block with the uncorrectable error and then relocates the data to a newly allocated memory block to replace the memory block with the uncorrectable error.
摘要:
A soft lock mechanism controls access by multiple processes to a shared resource to make simultaneous access an unlikely event, while not necessarily preventing simultaneous access. Preferably, the soft lock contains a next_free_time field, specifying when the soft lock will next be available, and a lock_duration, specifying a sufficiently long interval for most accesses to the resource to complete. The lock is obtained by comparing the current time to next_free_time. If the current time is later than next_free_time, then the lock is obtained immediately, and next_free_time is updated to the current time plus lock_duration. If the current time is before next_free_time, then next_free_time is incremented by lock_duration, and the requesting process waits until the old next_free_time to obtain the lock. No action is required to release the lock.
摘要:
A method and computer program product are provided for implementing highly concurrent record insertion in an ordinal number dependent database. Serialized processing is provided with one concurrent task of multiple concurrent tasks allowed to execute, for allocation of ordinal numbers for record insertion. Concurrent validation processing operations of multiple concurrent tasks are enabled for record insertion in the ordinal number dependent database. A set of counter variables are maintained with the database to enable removal of serialization from the validation phase processing operations for record insertion in the ordinal number dependent database.
摘要:
A soft lock mechanism controls access by multiple processes to a shared resource to make simultaneous access an unlikely event, while not necessarily preventing simultaneous access. Preferably, the soft lock contains a next_free_time field, specifying when the soft lock will next be available, and a lock_duration, specifying a sufficiently long interval for most accesses to the resource to complete. The lock is obtained by comparing the current time to next_free_time. If the current time is later than next_free_time, then the lock is obtained immediately, and next_free_time is updated to the current time plus lock_duration. If the current time is before next_free_time, then next_free_time is incremented by lock_duration, and the requesting process waits until the old next_free_time to obtain the lock. No action is required to release the lock.