Abstract: Some embodiments of the invention provide techniques whereby a user may perform a system reset (e.g., to address system performance and/or reliability degradation, such as which may be caused by unused applications that unnecessarily consume system resources, an attempted un-install of an application that left remnants of the application behind, and/or other causes). In some embodiments, performing a system reset replaces a first instance of an operating system on the system with a new instance of the operating system, and removes any applications installed on the system, without disturbing the user's data.

Abstract: Some embodiments of the invention provide techniques whereby a user may perform a system reset (e.g., to address system performance and/or reliability degradation, such as which may be caused by unused applications that unnecessarily consume system resources, an attempted un-install of an application that left remnants of the application behind, and/or other causes). In some embodiments, performing a system reset replaces a first instance of an operating system on the system with a new instance of the operating system, and removes any applications installed on the system, without disturbing the user's data.

Abstract: Some embodiments of the invention provide techniques whereby a user may perform a system reset (e.g., to address system performance and/or reliability degradation, such as which may be caused by unused applications that unnecessarily consume system resources, an attempted un-install of an application that left remnants of the application behind, and/or other causes). In some embodiments, performing a system reset replaces a first instance of an operating system on the system with a new instance of the operating system, and removes any applications installed on the system, without disturbing the user's data.

Abstract: Some embodiments of the invention provide techniques whereby a user may perform a system reset (e.g., to address system performance and/or reliability degradation, such as which may be caused by unused applications that unnecessarily consume system resources, an attempted un-install of an application that left remnants of the application behind, and/or other causes). In some embodiments, performing a system reset replaces a first instance of an operating system on the system with a new instance of the operating system, and removes any applications installed on the system, without disturbing the user's data.

Abstract: To improve identifying and tracking errors on a computer, an operating system for a computer is programmed to have a framework allowing programmable monitors of events to be defined. These programmable monitors are programmed to detect one or more events or patterns of events, and have associated actions. When the pattern of events occurs, the monitor is triggered, and actions associated with the monitor can be performed. Various actions can be performed, including but not limited to data gathering about the events triggering the monitor, other events occurring during the same time period, and information about the configuration of the computer. Monitors can be dynamically updated remotely during operation of the computer. An operating system can be programmed to have any number of such monitors. Similarly, the actions that occur when a monitor is triggered also can be dynamically updated.

Abstract: Some embodiments of the invention provide techniques whereby a user may perform a system reset (e.g., to address system performance and/or reliability degradation, such as which may be caused by unused applications that unnecessarily consume system resources, an attempted un-install of an application that left remnants of the application behind, and/or other causes). In some embodiments, performing a system reset replaces a first instance of an operating system on the system with a new instance of the operating system, and removes any applications installed on the system, without disturbing the user's data.

Abstract: Some embodiments of the invention provide techniques for performing system reset and/or system restore operations. Some embodiments store a record of any changes performed to a data file stored on a virtual hard disk using differencing virtual disks that are captured over time. To restore the file to the state in which it existed at any particular point in time, embodiments of the invention may allow for rolling back the system to a differencing virtual disk captured at or before that time and setting aside blocks of the differencing virtual disk chain captured after that point. To perform a system reset, the system may be rolled back to the parent virtual hard disk, by setting aside all of the blocks of the differencing virtual disk chain. Some embodiments of the invention provide for separating information on the system into a plurality of entities, and maintaining a separate set of differencing virtual disks for each entity.

Abstract: Some embodiments of the invention provide techniques whereby a user may perform a system reset (e.g., to address system performance and/or reliability degradation, such as which may be caused by unused applications that unnecessarily consume system resources, an attempted un-install of an application that left remnants of the application behind, and/or other causes). In some embodiments, performing a system reset replaces a first instance of an operating system on the system with a new instance of the operating system, and removes any applications installed on the system, without disturbing the user's data.

Abstract: Some embodiments of the invention provide techniques whereby a user may perform a system reset (e.g., to address system performance and/or reliability degradation, such as which may be caused by unused applications that unnecessarily consume system resources, an attempted un-install of an application that left remnants of the application behind, and/or other causes). In some embodiments, performing a system reset replaces a first instance of an operating system on the system with a new instance of the operating system, and removes any applications installed on the system, without disturbing the user's data.

Abstract: A method of detecting a network hang and restoring an application that communicates on a connection giving rise to the network hang. A user experience may be improved by providing the user with an option to restore the hung application without losing unsaved data or state information. The network hang may be detected when the user tries to terminate the application. The method may include determining whether the network hang is recoverable, which may involve diagnosing a type of the hang. If recoverable, a network connection reset mechanism may be triggered by instructing a network stack of the computer to terminate the network connection.

Abstract: Some embodiments of the invention provide components and/or techniques that may assist in choosing a snapshot to which to roll back to address a system malfunction. For example, some embodiments of the invention may record various metrics describing the system's performance, reliability and/or functionality at the points at which various snapshots are taken, along any of numerous dimensions. When a user later indicates a desire to restore the system to a previous point, these metrics may be analyzed to choose a snapshot to which to roll back.

Abstract: Some embodiments of the invention provide techniques for performing system reset and/or system restore operations. Some embodiments store a record of any changes performed to a data file stored on a virtual hard disk using differencing virtual disks that are captured over time. To restore the file to the state in which it existed at any particular point in time, embodiments of the invention may allow for rolling back the system to a differencing virtual disk captured at or before that time and setting aside blocks of the differencing virtual disk chain captured after that point. To perform a system reset, the system may be rolled back to the parent virtual hard disk, by setting aside all of the blocks of the differencing virtual disk chain. Some embodiments of the invention provide for separating information on the system into a plurality of entities, and maintaining a separate set of differencing virtual disks for each entity.

Abstract: Some embodiments of the invention provide techniques whereby a user may perform a system reset (e.g., to address system performance and/or reliability degradation, such as which may be caused by unused applications that unnecessarily consume system resources, an attempted un-install of an application that left remnants of the application behind, and/or other causes). In some embodiments, performing a system reset replaces a first instance of an operating system on the system with a new instance of the operating system, and removes any applications installed on the system, without disturbing the user's data.

Abstract: A method of detecting a network hang and restoring an application that communicates on a connection giving rise to the network hang. A user experience may be improved by providing the user with an option to restore the hung application without losing unsaved data or state information. The network hang may be detected when the user tries to terminate the application. The method may include determining whether the network hang is recoverable, which may involve diagnosing a type of the hang. If recoverable, a network connection reset mechanism may be triggered by instructing a network stack of the computer to terminate the network connection.

Abstract: A method of detecting a network hang and restoring an application that communicates on a connection giving rise to the network hang. A user experience may be improved by providing the user with an option to restore the hung application without losing unsaved data or state information. The network hang may be detected when the user tries to terminate the application. The method may include determining whether the network hang is recoverable, which may involve diagnosing a type of the hang. If recoverable, a network connection reset mechanism may be triggered by instructing a network stack of the computer to terminate the network connection.

Abstract: A method of detecting a network hang and restoring an application that communicates on a connection giving rise to the network hang. A user experience may be improved by providing the user with an option to restore the hung application without losing unsaved data or state information. The network hang may be detected when the user tries to terminate the application. The method may include determining whether the network hang is recoverable, which may involve diagnosing a type of the hang. If recoverable, a network connection reset mechanism may be triggered by instructing a network stack of the computer to terminate the network connection.

Abstract: A computer configured for managing multiple processing threads is susceptible to deadlocks or hangs when resources needed by one process are locked by another process that is not progressing. Locking relationships are created and released so quickly that rigidly monitoring these relationships would consume more computer power than are being monitored. An approach to determining the existence of a deadlock or hang uses a first ‘snapshot’ showing an approximation of locking relationships and then verifies a deadlock or hang using a second snapshot to determine if a suspected deadlock or hang is still present.

Abstract: An application programming interface (API) that leverages operating system instrumentation to provide a chain of threads and processes may alleviate some debugging complications. Specifically, the chain may start with the first thread in the process that experienced the original failure and end with the last thread upon which the first thread directly or indirectly depends. The API may aid debugging efforts by classifying all threads related or dependent upon an original failed thread into specific categories of failures, requesting further information from the originating OS concerning specific failed threads, and using that information to debug the failed application or process more thoroughly.

Abstract: A virtual file system and method. The system architecture enables a plurality of underlying file systems running on various file servers to be “virtualized” into one or more “virtual volumes” that appear as a local file system to clients that access the virtual volumes. The system also enables the storage spaces of the underlying file systems to be aggregated into a single virtual storage space, which can be dynamically scaled by adding or removing file servers without taking any of the file systems offline and in a manner transparent to the clients. This functionality is enabled through a software “virtualization” filter on the client that intercepts file system requests and a virtual file system driver on each file server. The system also provides for load balancing file accesses by distributing files across the various file servers in the system, through migration of data files between servers.