摘要:
In an implementation, a system includes a simulation engine that is executable to simulate actions performed by a plurality of devices in a distributed system. The system also includes a plurality of pluggable device models that are accessible by the simulation engine via an interface. Each of the device models represents one of the devices and is configured to map a cost of performing at least one of the actions to an action latency by the corresponding device.
摘要:
Simulating device interactions. A method may be practiced in a computing system for simulating interconnected devices. The method of simulating device interactions may be done in performing an overall transaction to obtain an output of system performance characteristics including measurement of latencies and/or device loads for actions performed by devices in performing the overall transaction. The method includes dividing a transaction into individual actions. The actions are applied to appropriate device models to produce latencies and/or device utilizations for the action as applied to the appropriate device model. This may be done by including an indication of an action type and optionally an action subservice. Memory resources may be conserved by ending the simulation when latencies and/or device utilizations have settled. Device utilization and latency may be aggregated and averaged over time. When changes in the latencies and/or device utilizations are within a predetermined range, the simulation can be ended.
摘要:
A method and system for defining performance models of distributed applications such as distributed systems or network systems in a way that combines discrete and analytical models and simulating such performance models for analyzing software performance and impacts on devices of the distributed applications is described. Also described is a method for accelerating the simulation process by converting the discrete load into aggregate load dynamically based on the statistical analysis of the simulation results.
摘要:
Disclosed is a method, and apparatus implementing that method, for synchronizing and managing the "system clocks" maintained by each of a number of processor units forming a multiprocessor system. Based on an averaging technique, the method includes creating a synchronization message by an originator processor unit and routing that message to other of the processor units to obtain clock values representative of each of the system clocks of each processor unit. The average clock value is then determined and that average clock value then rerouted to each of the processor units to permit them to update, if necessary, their individual system clocks to the average of all. The method further includes determining the transit times encountered by the various messages so that each processor unit can adjust the average clock value it will use to update or synchronize its system clock to account for such transit times.
摘要:
A design tool includes a service definition model to enable abstract description of distributed computing systems and distributed applications. The design tool also includes a schema to dictate how functional operations within the service definition model are to be specified. The functional operations include design of distributed applications, deployment of distributed applications, and management of distributed applications.
摘要:
A design tool includes a service definition model to enable abstract description of distributed computing systems and distributed applications. The design tool also includes a schema to dictate how functional operations within the service definition model are to be specified. The functional operations include design of distributed applications, deployment of distributed applications, and management of distributed applications.
摘要:
A method and system wherein following a partitioning of a server cluster, operational subgroups arbitrate for possession of a quorum resource that determines cluster representation, wherein the arbitration is biased by a relative weight of the subgroup. The weight may be relative to the original cluster weight, or submitted as a bid that is relative to other possible subgroup weights. The biasing gives subgroups that are better capable of representing the cluster an arbitration advantage over lesser subgroups. The biasing weight of each subgroup may be determined by node count and/or by a calculation of the subgroup's resources. The arbitration may be delayed based on the relative weight, or alternatively, the arbitration may comprise a bidding process in which a subgroup's bid is based on the subgroup's relative weight.
摘要:
A method and apparatus for measuring relative heading changes in a vehicular onboard navigation system is provided comprising apparatus for providing signals corresponding to differential wheel distance measurements, the velocity and wheel tracking distance of the vehicle. When front wheel distance measurements are used in a vehicle having an Ackerman-type steering system, an apparatus for providing a signal corresponding to an effective front wheel tracking distance as a function of the curvature of turn is also provided.
摘要:
Data records containing one or more fields, which can be considered keys and/or values, are received, and processed such that data values of records that contain key values of interest are aggregated together. The keys of the resultant aggregations or “resultant keys” are created under the control of simple parameters to an aggregation framework. Similarly, the particular aggregations performed are also under the control of a similar set of simple parameters to the aggregation framework. Mapping of keys to reduce originality is one of the important features of resultant key creation. Finally, the structure of the parameters used to control aggregation is simple, flexible, and powerful.
摘要:
Data records containing one or more fields, which can be considered keys and/or values, are received, and processed such that data values of records that contain key values of interest are aggregated together. The keys of the resultant aggregations or “resultant keys” are created under the control of simple parameters to an aggregation framework. Similarly, the particular aggregations performed are also under the control of a similar set of simple parameters to the aggregation framework. Mapping of keys to reduce originality is one of the important features of resultant key creation. Finally, the structure of the parameters used to control aggregation is simple, flexible, and powerful.