Abstract: A system to improve cluster machine processing that may include a plurality of interconnected computers that process data as one if necessary, and at least one other plurality of interconnected computers that process data as one if necessary. The system may also include a central manager to control what data processing is performed on a shared processing job performed by the plurality of interconnected computers and the at least one other plurality of interconnected computers. Each of the plurality of interconnected computers runs parallel jobs scheduled by a local backfill scheduler. In order to schedule a cluster spanning parallel job, the local schedulers cooperate on placement and timing of the cluster spanning job, using existing backfill rules in order not to disturb the local job streams.

Abstract: A computing system configured to handle preemption events in an environment having jobs with high and low priorities. The system includes a job queue configured to receive job requests from users, the job queue storing the jobs in an order based on the priority of the jobs, and indicating whether a job is a high priority job or a low priority job. The system also includes a plurality of node clusters, each node cluster including a plurality of nodes and a scheduler coupled to the job queue and to the plurality of node clusters and configured to assign jobs from the job queue to the plurality of node clusters.

Abstract: Backfill scheduling techniques are used to schedule execution of applications, either on a local computing unit or a remote unit. In determining whether a particular application is to be scheduled to execute on a local unit or a remote unit, the data associated with that application is considered. As examples, an amount of data to be moved, availability of communication channels, and/or availability of remote data storage resources are considered.

Abstract: A system and computer program product that off-loads the processing associated with responding to user status requests for software task execution queues or for queued software tasks that are managed by a software task manager. A software task manager is periodically queried for status and the results of that periodic query are stored in a file. User queries for the status of the software task manager are handled by a separate process on a separate computing node. Queries submitted by users for the status of queues or queued software tasks managed by the software task manager are satisfied by retrieving the status data that are stored in the file. Alternative embodiments distribute copies of the file to several computing nodes to further alleviate the processing bottleneck caused by responding to frequent task manager status queries from many users.

Abstract: A method, grid computing environment, and computer readable medium for managing available resources in a grid computing environment are disclosed. The method includes determining, when a new job is submitted, if a first of the computing clusters has sufficient available resources to run the new job. If the first computing cluster does not have sufficient available resources to run the new job, the method further includes determining if a second of the computing clusters has sufficient available resources to run a first job that is currently running on the first computing cluster. If the second computing cluster has sufficient available resources to run the first job, the first job is migrated to the second computing cluster.

Abstract: A facility is presented for scheduling computer jobs of a computing environment having a plurality of computing nodes. The facility includes scheduling N sequential computer jobs of a job queue until achieving a top job party, wherein N?2, and the number of jobs in the top job party is dynamically determined by monitoring backfill window coverage of the computing nodes by the N scheduled jobs and automatically closing membership in the top job party once (i) all computing nodes are covered by at least one backfill window, or (ii) a backfill end time of at least one computing node is greater than or equal to a maximum wallclock limit of a set of job classes having the N scheduled jobs. Responsive to determining the top job party, the facility then backfill schedules jobs of the job queue around the top job party for execution.

Abstract: A system to improve cluster machine processing that may include a plurality of interconnected computers that process data as one if necessary, and at least one other plurality of interconnected computers that process data as one if necessary. The system may also include a central manager to control what data processing is performed on a shared processing job performed by the plurality of interconnected computers and the at least one other plurality of interconnected computers. Each of the plurality of interconnected computers runs parallel jobs scheduled by a local backfill scheduler. In order to schedule a cluster spanning parallel job, the local schedulers cooperate on placement and timing of the cluster spanning job, using existing backfill rules in order not to disturb the local job streams.

Abstract: A computing system configured to handle preemption events in an environment having jobs with high and low priorities. The system includes a job queue configured to receive job requests from users, the job queue storing the jobs in an order based on the priority of the jobs, and indicating whether a job is a high priority job or a low priority job. The system also includes a plurality of node clusters, each node cluster including a plurality of nodes and a scheduler coupled to the job queue and to the plurality of node clusters and configured to assign jobs from the job queue to the plurality of node clusters.

Abstract: A method is provided for starting a job in a parallel batch job data processing system in which a job is submitted to a scheduler having available, for use, a plurality of resource classes in the data processing system and by also including, within the job, instructions which cause notification of job starting to the scheduler and then, upon this notification, removing the job from all but the first resource class on which it is started.

Abstract: The security of data is enhanced by the use of cyclic redundancy checks. Data is encoded with one or more cyclic redundancy checks and then transmitted by a transmitter to a receiver. The receiver receives the encoded data and decodes it in order to use the one or more cyclic redundancy checks to determine whether the data was sent by an authorized user.

Abstract: A system and computer program product that off-loads the processing associated with responding to user status requests for software task execution queues or for queued software tasks that are managed by a software task manager. A software task manager is periodically queried for status and the results of that periodic query are stored in a file. User queries for the status of the software task manager are handled by a separate process on a separate computing node. Queries submitted by users for the status of queues or queued software tasks managed by the software task manager are satisfied by retrieving the status data that are stored in the file. Alternative embodiments distribute copies of the file to several computing nodes to further alleviate the processing bottleneck caused by responding to frequent task manager status queries from many users.

Abstract: A method that off-loads the processing associated with responding to user status requests for software task execution queues or for queued software tasks that are managed by a software task manager. A software task manager is periodically queried for status and the results of that periodic query are stored in a file. User queries for the status of the software task manager are handled by a separate process that can operate on the same or on a separate computing node than is hosting the software task manager. Queries submitted by users for the status of queues or queued software tasks managed by the software task manager are satisfied by retrieving the status data that are stored in the file. Alternative embodiments distribute copies of the file to several computing nodes to further alleviate the processing bottleneck caused by responding to frequent task manager status queries from many users.

Abstract: A method, grid computing environment, and computer readable medium for managing available resources in a grid computing environment are disclosed. The method includes determining, when a new job is submitted, if a first of the computing clusters has sufficient available resources to run the new job. If the first computing cluster does not have sufficient available resources to run the new job, the method further includes determining if a second of the computing clusters has sufficient available resources to run a first job that is currently running on the first computing cluster. If the second computing cluster has sufficient available resources to run the first job, the first job is migrated to the second computing cluster.

Abstract: Backfill scheduling techniques are used to schedule execution of applications, either on a local computing unit or a remote unit. In determining whether a particular application is to be scheduled to execute on a local unit or a remote unit, the data associated with that application is considered. As examples, an amount of data to be moved, availability of communication channels, and/or availability of remote data storage resources are considered.

Abstract: A method is provided for scheduling software task execution. According to the method, at least one high priority software task that has a specified start time and at least one lower priority software task are accepted. There is determined a time remaining until the specified start time for the high priority software task, and there is determined if the lower priority software task can complete execution within the time remaining that was determined. The lower priority software task is executed only if it was determined to be able to complete execution within the time remaining, and the high priority software task is executed at or very near the specified start time. In a preferred embodiment, all incoming software tasks are placed on a task queue with a status of hold to prevent execution.

Abstract: Backfill scheduling techniques are used to schedule execution of applications, either on a local computing unit or a remote unit. In determining whether a particular application is to be scheduled to execute on a local unit or a remote unit, the data associated with that application is considered. As examples, an amount of data to be moved, availability of communication channels, and/or availability of remote data storage resources are considered.

Abstract: A method is provided for scheduling software task execution. According to the method, at least one high priority software task that has a specified start time and at least one lower priority software task are accepted. There is determined a time remaining until the specified start time for the high priority software task, and there is determined if the lower priority software task can complete execution within the time remaining that was determined. The lower priority software task is executed only if it was determined to be able to complete execution within the time remaining, and the high priority software task is executed at or very near the specified start time. In a preferred embodiment, all incoming software tasks are placed on a task queue with a status of hold to prevent execution.

Abstract: A method and system that off-loads the processing associated with responding to user status requests for software task execution queues or for queued software tasks that are managed by a software task manager. A software task manager is periodically queried for status and the results of that periodic query are stored in a file. User queries for the status of the software task manager are handled by a separate process that can operate on the same or on a separate computing node than is hosting the software task manager. Queries submitted by users for the status of queues or queued software tasks managed by the software task manager are satisfied by retrieving the status data that are stored in the file. Alternative embodiments distribute copies of the file to several computing nodes to further alleviate the processing bottleneck caused by responding to frequent task manager status queries from many users.

Abstract: A system and method for manipulating waveforms, including transaction cancellation, in parallel time-warp simulation of circuits, such as those modeled in VHDL. Events waveforms for each output of a processor are organized by the simulation time (ST) of the events which created them and by the simulation time (RT) at which they are to be effective. A phantom buffer provides a linked list of events and associated transactions cancelled as a result of insertion of a new event in said chain of events. Rollback of a cancelled event waveform is done by restoring to the linked lists selected events and transactions from the phantom buffer.

Abstract: System and method for calculating global virtual time for use in memory management, termination detection, snapshots, crash recovery, input and output handling, and so forth, and in parallel simulation of digital circuits. Processes executing on parallel processors communicate messages through channels having output trail buffers on each process communicating to the channel, and one input trail buffer for all processes receiving messages from the channel. A channel is the union of all wires or communication paths connecting two processors. Input trail buffers store the time stamp of the most recently received message, and output trail buffers store valley messages. Global virtual time is calculated with reference to the least time stamp of the output trail buffers, where the least time stamp is calculated with respect to the time stamp of the input trail buffer.