Abstract: A method and an apparatus for characterizing performance of a device based on user-perceivable latency. To characterize device performance, a value of a metric may be computed from latencies of operations performed by the device. In computing a value of a metric, latencies may be treated differently, such that some latencies perceivable by a user of the device may have a greater impact on the value of the metric than other latencies that either are not perceivable or are perceived by the user to a lesser degree. Such a performance metric based on user-perceivable latency facilitates identification of computing device that provide a desirable user experience.

Abstract: A method and an apparatus for characterizing performance of a device based on user-perceivable latency. To characterize device performance, a value of a metric may be computed from latencies of operations performed by the device. In computing a value of a metric, latencies may be treated differently, such that some latencies perceivable by a user of the device may have a greater impact on the value of the metric than other latencies that either are not perceivable or are perceived by the user to a lesser degree. Such a performance metric based on user-perceivable latency facilitates identification of computing device that provide a desirable user experience.

Abstract: A method and an apparatus for characterizing performance of a device based on user-perceivable latency. To characterize device performance, a value of a metric may be computed from latencies of operations performed by the device. In computing a value of a metric, latencies may be treated differently, such that some latencies perceivable by a user of the device may have a greater impact on the value of the metric than other latencies that either are not perceivable or are perceived by the user to a lesser degree. Such a performance metric based on user-perceivable latency facilitates identification of computing device that provide a desirable user experience.

Abstract: Techniques for storage device power management are described that enable coordinated buffer flushing and power management for storage devices. In various embodiments, a power manager can coordinate the flushing of pending or “dirty” data from multiple buffers of a computing device in order to reduce or eliminate interleaved (e.g., uncoordinated) data operations from the multiple buffers that can cause shortened disk idle periods. By so doing, the power manager can selectively manage power states for one or more power-managed storage devices to produce longer idle periods. For example, information regarding the status of multiple buffers can be used in conjunction with analysis of historical I/O patterns to determine appropriate times to spin down a disk or allow the disk to keep spinning. Additionally, user-presence information can be utilized to tune the aggressiveness of buffer coordination and state transitions for power-managed storage devices to improve performance.

Abstract: A method and an apparatus for characterizing performance of a device based on user-perceivable latency. To characterize device performance, a value of a metric may be computed from latencies of operations performed by the device. In computing a value of a metric, latencies may be treated differently, such that some latencies perceivable by a user of the device may have a greater impact on the value of the metric than other latencies that either are not perceivable or are perceived by the user to a lesser degree. Such a performance metric based on user-perceivable latency facilitates identification of computing device that provide a desirable user experience.

Abstract: Techniques for user input triggered device power management are described that enable user inputs and activities to cause selective changes in power states for a device. Power can be boosted to a high power state to improve responsiveness for designated inputs and/or activities. When responsiveness is deemed less important in connection with particular inputs and/or activities, a low power state can be set to reduce energy consumption. In at least some embodiments, selectively switching between power states includes detecting various user inputs at a device and filtering the inputs to select power states associated with the user inputs. The device can then be operated in a selected power state until a transition to a different power state is triggered by occurrence of designated events, such as running of a set time interval, further user input, and/or completion of user activity.

Abstract: Techniques for storage device power management are described that enable coordinated buffer flushing and power management for storage devices. In various embodiments, a power manager can coordinate the flushing of pending or “dirty” data from multiple buffers of a computing device in order to reduce or eliminate interleaved (e.g., uncoordinated) data operations from the multiple buffers that can cause shortened disk idle periods. By so doing, the power manager can selectively manage power states for one or more power-managed storage devices to produce longer idle periods. For example, information regarding the status of multiple buffers can be used in conjunction with analysis of historical I/O patterns to determine appropriate times to spin down a disk or allow the disk to keep spinning. Additionally, user-presence information can be utilized to tune the aggressiveness of buffer coordination and state transitions for power-managed storage devices to improve performance.

Abstract: A method of, a computer program product for and a computer system for managing statistics in a database management system are provided. A value of a volatility of a statistic is determined. A value of a staleness of the statistic is determined using the value of the volatility. A statistics collection task is generated in response to, at least in part, the value of the staleness exceeding a value of a staleness threshold. The statistics collection task is executed to collect an additional value of the statistic. The additional value of the statistic is stored.

Abstract: An apparatus and method are provided for power management in a computer operating system. The method includes providing a plurality of policies which are eligible to be selected for a component, automatically selecting one of the eligible policies to manage the component, and activating the selected policy to manage the component while the system is running without rebooting the system.

Abstract: Various embodiments of a method, apparatus and article of manufacture of managing statistics in a database management system are provided. A volatility of at least one of statistic is determined. One or more statistics collection tasks are generated based on, at least in part, the volatility.