Abstract: The output of a non-deterministic instruction is handled during record and replay in a virtual machine. An output of a non-deterministic instruction is stored to a buffer during record mode and retrieved from a buffer during replay mode without exiting to the hypervisor. At least part of the contents of the buffer can be stored to a log when the buffer is full during record mode, and the buffer can be replenished from a log when the buffer is empty during replay mode.

Abstract: Autonomous selection between multiple virtualization techniques implemented in a virtualization layer of a virtualized computer system. The virtual machine monitor implements multiple virtualization support processors that each provide for the comprehensive handling of potential virtualization exceptions. A virtual machine monitor resident virtualization selection control is operable to select between use of first and second virtualization support processors dependent on identifying a predetermined pattern of temporally local privilege dependent instructions within a portion of an instruction stream as encountered in the execution of a guest operating system.

Abstract: Autonomous selection between multiple virtualization techniques implemented in a virtualization layer of a virtualized computer system. The virtual machine monitor implements multiple virtualization support processors that each provide for the comprehensive handling of potential virtualization exceptions. A virtual machine monitor resident virtualization selection control is operable to select between use of first and second virtualization support processors dependent on identifying a predetermined pattern of temporally local privilege dependent instructions within a portion of an instruction stream as encountered in the execution of a guest operating system.

Abstract: The output of a non-deterministic instruction is handled during record and replay in a virtual machine. An output of a non-deterministic instruction is stored to a buffer during record mode and retrieved from a buffer during replay mode without exiting to the hypervisor. At least part of the contents of the buffer can be stored to a log when the buffer is full during record mode, and the buffer can be replenished from a log when the buffer is empty during replay mode.

Abstract: Autonomous selection between multiple virtualization techniques implemented in a virtualization layer of a virtualized computer system. The virtual machine monitor implements multiple virtualization support processors that each provide for the comprehensive handling of potential virtualization exceptions. A virtual machine monitor resident virtualization selection control is operable to select between use of first and second virtualization support processors dependent on identifying a predetermined pattern of temporally local privilege dependent instructions within a portion of an instruction stream as encountered in the execution of a guest operating system.

Abstract: The output of a non-deterministic instruction is handled during record and replay in a virtual machine. An output of a non-deterministic instruction is stored to a buffer during record mode and retrieved from a buffer during replay mode without exiting to the hypervisor. At least part of the contents of the buffer can be stored to a log when the buffer is full during record mode, and the buffer can be replenished from a log when the buffer is empty during replay mode.

Abstract: Autonomous selection between multiple virtualization techniques implemented in a virtualization layer of a virtualized computer system. The virtual machine monitor implements multiple virtualization support processors that each provide for the comprehensive handling of potential virtualization exceptions. A virtual machine monitor resident virtualization selection control is operable to select between use of first and second virtualization support processors dependent on identifying a predetermined pattern of temporally local privilege dependent instructions within a portion of an instruction stream as encountered in the execution of a guest operating system.

Abstract: Autonomous selection between multiple virtualization techniques implemented in a virtualization layer of a virtualized computer system. The virtual machine monitor implements multiple virtualization support processors that each provide for the comprehensive handling of potential virtualization exceptions. A virtual machine monitor resident virtualization selection control is operable to select between use of first and second virtualization support processors dependent on identifying a predetermined pattern of temporally local privilege dependent instructions within a portion of an instruction stream as encountered in the execution of a guest operating system.

Abstract: Automatically aligning virtual blocks of partitions to blocks of underlying physical storage is disclosed. In some embodiments, a starting offset of a partition included in a logical container is detected. In some embodiments, a misalignment correction amount for a partition included in a logical container is detected. In some embodiments, a misalignment associated with a partition included in a logical container is corrected.

Abstract: A method for precisely counting guest branch instructions in a virtualized computer system is described. In one embodiment, guest instructions execute in a direct execution mode of the virtualized computer system. The direct execution mode operates at a first privilege level having a lower privilege than a second privilege level. A branch count of previously executed first privilege level branch instructions is maintained as instructions execute. Execution of a first privilege level branch instruction caused by a control transfer to the direct execution mode is detected. Responsive to the detection, a guest branch instruction count is determined based on the first privilege level branch count.

Abstract: Automatically aligning virtual blocks of partitions to blocks of underlying physical storage is disclosed. In some embodiments, a starting offset of a partition included in a logical container is detected. In some embodiments, a misalignment correction amount for a partition included in a logical container is detected. In some embodiments, a misalignment associated with a partition included in a logical container is corrected.

Abstract: Automatically aligning virtual blocks of partitions to blocks of underlying physical storage is disclosed. In some embodiments, a starting offset of a first partition included in a logical container is detected. In some embodiments, a misalignment correction amount for a first partition included in a logical container is detected. In some embodiments, a misalignment associated with a first partition included in a logical container is corrected.

Abstract: One embodiment is a computer-implemented method of trace collection for a virtual machine that includes: executing a sequence of instructions from an initial state of the virtual machine; accessing an event log of data relating to nondeterministic events, which data includes an execution point; making at least a portion of the data available to the virtual machine when the sequence reaches the execution point; collecting trace information in response to expansion parameters; and storing the trace information in a trace file.

Abstract: Autonomous selection between multiple virtualization techniques implemented in a virtualization layer of a virtualized computer system. The virtual machine monitor implements multiple virtualization support processors that each provide for the comprehensive handling of potential virtualization exceptions. A virtual machine monitor resident virtualization selection control is operable to select between use of first and second virtualization support processors dependent on identifying a predetermined pattern of temporally local privilege dependent instructions within a portion of an instruction stream as encountered in the execution of a guest operating system.

Abstract: The output of a non-deterministic instruction is handled during record and replay in a virtual machine. An output of a non-deterministic instruction is stored to a buffer during record mode and retrieved from a buffer during replay mode without exiting to the hypervisor. At least part of the contents of the buffer can be stored to a log when the buffer is full during record mode, and the buffer can be replenished from a log when the buffer is empty during replay mode.

Abstract: Autonomous selection between multiple virtualization techniques implemented in a virtualization layer of a virtualized computer system. The virtual machine monitor implements multiple virtualization support processors that each provide for the comprehensive handling of potential virtualization exceptions. A virtual machine monitor resident virtualization selection control is operable to select between use of first and second virtualization support processors dependent on identifying a predetermined pattern of temporally local privilege dependent instructions within a portion of an instruction stream as encountered in the execution of a guest operating system.

Abstract: The output of a non-deterministic instruction is handled during record and replay in a virtual machine. An output of a non-deterministic instruction is stored to a buffer during record mode and retrieved from a buffer during replay mode without exiting to the hypervisor. At least part of the contents of the buffer can be stored to a log when the buffer is full during record mode, and the buffer can be replenished from a log when the buffer is empty during replay mode.

Abstract: A data storage system is disclosed, including: a first storage device of a first storage device type, a second storage device of a second storage device type, and a processor configured to implement a hybrid file system configured to store each of a plurality of data values in at least a corresponding primary location, which for a given data value may be in either the first storage device or the second storage device; wherein the hybrid file system is configured to use a first access approach optimized based on a first access attribute of the first storage device type to interact with the first storage device and a second access approach optimized based on a second access attribute of the second storage device type to interact with the second storage device.

Abstract: A method and computer program product for logging non-deterministic events of a virtual machine executing a sequence guest instructions, the method including tracking an execution point in the sequence of executing guest instructions, the tracking of the execution point including determining a branch count of executed branch instructions; and detecting an occurrence of a non-deterministic event directed to the virtual machine during execution of the sequence of guest instructions, and recording information which includes an identifier of a current execution point, wherein the identifier includes the branch count.

Abstract: The output of a non-deterministic instruction is handled during record and replay in a virtual machine. An output of a non-deterministic instruction is stored to a buffer during record mode and retrieved from a buffer during replay mode without exiting to the hypervisor. At least part of the contents of the buffer can be stored to a log when the buffer is full during record mode, and the buffer can be replenished from a log when the buffer is empty during replay mode.