545 results about "Context switch" patented technology

A virtualization infrastructure that allows multiple guest partitions to run within a host hardware partition. The host system is divided into distinct logical or virtual partitions and special infrastructure partitions are implemented to control resource management and to control physical I / O device drivers that are, in turn, used by operating systems in other distinct logical or virtual guest partitions. Host hardware resource management runs as a tracking application in a resource management “ultravisor” partition, while host resource management decisions are performed in a higher level command partition based on policies maintained in a separate operations partition. The conventional hypervisor is reduced to a context switching and containment element (monitor) for the respective partitions, while the system resource management functionality is implemented in the ultravisor partition. The ultravisor partition maintains the master in-memory database of the hardware resource allocations and serves a command channel to accept transactional requests for assignment of resources to partitions. It also provides individual read-only views of individual partitions to the associated partition monitors. Host hardware I / O management is implemented in special redundant I / O partitions. Operating systems in other logical or virtual partitions communicate with the I / O partitions via memory channels established by the ultravisor partition. The guest operating systems in the respective logical or virtual partitions are modified to access monitors that implement a system call interface through which the ultravisor, I / O, and any other special infrastructure partitions may initiate communications with each other and with the respective guest partitions. The guest operating systems are modified so that they do not attempt to use the “broken” instructions in the x86 system that complete virtualization systems must resolve by inserting traps. System resources are separated into zones that are managed by a separate partition containing resource management policies that may be implemented across nodes to implement a virtual data center.

A virtualization infrastructure that allows multiple guest partitions to run within a host hardware partition. The host system is divided into distinct logical or virtual partitions and special infrastructure partitions are implemented to control resource management and to control physical I / O device drivers that are, in turn, used by operating systems in other distinct logical or virtual guest partitions. Host hardware resource management runs as a tracking application in a resource management “ultravisor” partition, while host resource management decisions are performed in a higher level command partition based on policies maintained in a separate operations partition. The conventional hypervisor is reduced to a context switching and containment element (monitor) for the respective partitions, while the system resource management functionality is implemented in the ultravisor partition. The ultravisor partition maintains the master in-memory database of the hardware resource allocations and serves a command channel to accept transactional requests for assignment of resources to partitions. It also provides individual read-only views of individual partitions to the associated partition monitors. Host hardware I / O management is implemented in special redundant I / O partitions. Operating systems in other logical or virtual partitions communicate with the I / O partitions via memory channels established by the ultravisor partition. The guest operating systems in the respective logical or virtual partitions are modified to access monitors that implement a system call interface through which the ultravisor, I / O, and any other special infrastructure partitions may initiate communications with each other and with the respective guest partitions. The guest operating systems are modified so that they do not attempt to use the “broken” instructions in the x86 system that complete virtualization systems must resolve by inserting traps.

A method and system for power management including device controller-based device use evaluation and power-state control provides improved performance in a power-managed processing system. Per-device usage information is measured and evaluated during process execution and is retrieved from the device controller upon a context switch, so that upon reactivation of the process, the previous usage evaluation state can be restored. The device controller can then provide for per-process control of attached device power management states without intervention by the processor and without losing the historical evaluation state when a process is switched out. The device controller can control power-saving states of connected devices in conformity with the usage evaluation without processor intervention and across multiple process execution slices. The device controller may be a memory controller and the controlled devices memory modules or banks within modules if individual banks can be power-managed. Local thresholds provide the decision-making mechanism for each controlled device. The thresholds may be history-based, fixed or adaptive and are generally set initially by the operating system and may be updated by the memory controller adaptively or using historical collected usage evaluation counts or alternatively by the operating system via a system processor.

A method for iteratively drilling-down on a user's textual free-form natural language query uses a session history to interpret successive queries in the context of previous queries on a topic or topics and to detect an implicit switch in topic. By maintaining a session history of the user's free-form natural language input and by automatically determining whether there is a topic or context switch, the search process is substantially simplified and is more effective; that is, more accurate answers to a user's queries are found faster. In addition, as the system operates on free-form natural language input, automatically constructing the actual search expressions, the complexity of constructing successive search expressions is obviated. If the system determines the user is, according to its session history and tests, asking successive questions within a given topic or context, the system keeps searching within a previously determined given set of previous responses on that context or topic. This effectively narrows the documents found allowing the user to quickly and accurately find just the documents of interest. If the system determines the user has implicitly changed context or topic, based on its session history and tests, it searches all the information at its disposal; i.e., all of the collections of documents.

A method and system for energy management in a simultaneous multi-threaded (SMT) processing system including per-thread device usage monitoring provides control of energy usage that accommodates thread parallelism. Per-device usage information is measured and stored on a per-thread basis, so that upon a context switch, the previous usage evaluation state can be restored. The per-thread usage information is used to adjust the thresholds of device energy management decision control logic, so that energy use can be managed with consideration as to which threads will be running in a given execution slice. A device controller can then provide for per-thread control of attached device power management states without intervention by the processor and without losing the historical evaluation state when a process is switched out. The device controller may be a memory controller and the controlled devices memory modules or banks within modules if individual banks can be power-managed. Local thresholds provide the decision-making mechanism for each controlled device and are adjusted by the operating system in conformity with the measured usage level for threads executing within the processing system. The per-thread usage information may be obtained from a performance monitoring unit that is located within or external to the device controller and the usage monitoring state is then retrieved and replaced by the operating system at each context switch.

A method is disclosed for recording and replaying computer programs. In one embodiment, a method of modifying a computer program to support recording execution, comprises the computer-implemented steps of receiving an executable application binary; modifying the executable application binary by adding one or more proxy code elements to result in creating a modified application binary, wherein upon execution of the modified application binary, the one or more proxy code elements create and store recorded information representing all non-deterministic events that occur during the execution. For example, asynchronous callbacks and thread context switches are recorded and can be replayed.

Multiplexing and demultiplexing are commonplace for an efficient bandwidth utilization in telecommunications. SRTS (Synchronous Residual Time Stamp) technique is widely used for timing recovery in processing of digital signal streams. The bit stuffing is also prevalent for various purposes, one being rate adjustment. The invention performs the SRTS technique entirely digitally to monitor the rate of slower speed signal streams in relation to the rate of a higher speed stream. The digital implementation permits the use of context switching for processing a plurality of digital signal streams. As the result, hardware requirement is greatly reduced.

Memory architecture provides capabilities for high performance content search. The architecture creates an innovative memory that can be programmed with content search rules which are used by the memory to evaluate presented content for matching with the programmed rules. When the content being searched matches any of the rules programmed in the Programmable Intelligent Search Memory (PRISM) action(s) associated with the matched rule(s) are taken. Content search rules comprise of regular expressions which are converted to finite state automata (FSA) and then programmed in PRISM for evaluating content with the search rules. PRISM architecture comprises of a plurality of programmable PRISM Search Engines (PSE) organized in PRISM memory clusters that are used simultaneously to search content presented to PRISM. A context switching architecture enables transitioning of PSE states between different input contexts.

The invention is directed to instrumenting object code of an application and / or an operating system on a target machine so that execution trace data can be generated, collected, and subsequently analyzed for various purposes, such as debugging and performance. Automatic instrumentation may be performed on an application's object code before, during or after linking. A target machine's operating system's object code can be manually or automatically instrumented. By identifying address space switches and thread switches in the operating system's object code, instrumented code can be inserted at locations that enable the execution trace data to be generated. The instrumentation of the operating system and application can enable visibility of total system behavior by enabling generation of trace information sufficient to reconstruct address space switches and context switches.