Abstract: A method for creating a virtual machine image, includes: storing a first image manifest for a first virtual machine image, the first image manifest including a mapping from file names of the first virtual machine image to content descriptors; storing a second image manifest for a second virtual machine image, the second image manifest including a mapping from file names of the second virtual machine image to content descriptors; creating a first overlay mapping by: placing a file name and its content descriptor both from the second image manifest in the first overlay mapping; and placing a file name and its content descriptor both from the first image manifest in the first overlay mapping if the file name and its content descriptor are not mapped in the second image manifest; and constructing a third virtual machine image having an image manifest whose mapping is the first overlay mapping.

Abstract: A method for operating a file system includes receiving a write instruction including a file descriptor associated with a file and a content identifier, a content offset, and a content length, associating a region within the file with the content identifier, saving the association of the region and the content identifier.

Abstract: A method for performing software operations on virtual machine images, includes: receiving a virtual machine image that includes data; reclassifying the data into a plurality of parts; and performing a software operation on one of the parts, wherein the software operation is performed without running a virtual machine.

Abstract: A method comprises receiving a first virtual machine image, processing the first virtual machine image with a Mirage transformation, and generating a first manifest including a mapping of hierarchical names of content of the first virtual machine image to content identifiers.

Abstract: A method for performing software operations on virtual machine images, includes: receiving a virtual machine image that includes a mapping from a first file name to first file content; reformatting the virtual machine image by: creating a store that contains the first file content and that associates a content descriptor with the first file content, wherein the first file content can be reconstructed by using the content descriptor; and decoupling the mapping by creating an image manifest that maps the first file name to the content descriptor; and performing a software operation on the virtual machine image using the reformatted virtual machine image.

Abstract: A method for performing software operations on virtual machine images, includes: receiving a first virtual machine image that includes a mapping from a first file name to first file content; reformatting the first virtual machine image by: creating a unique ID for the first file content; and decoupling the mapping of the first virtual machine image by creating an image manifest that maps the first file name to the unique ID, and creating a store that contains the first file content and that maps the unique ID to the first file content; and performing a software operation on the first virtual machine image using the reformatted first virtual machine image.

Abstract: Disclosed is a method, computer program product and a server unit of a virtual execution environment having at least one client. The server unit includes a network interface for conducting bidirectional communications with the at least one client and a control unit configured to determine, for individual ones of positions in a virtualized execution of an application, those components that are required at each position; to establish a pseudo-distance between the positions in the virtualized execution of the application; and to identify components that are candidates for prefetching as those components required at one or more positions that are proximate to a current position. The pseudo-distance between positions is indicative of an urgency of prefetching candidate components for regulating an amount of resources devoted to the prefetching of components.

Abstract: Disclosed is a method, apparatus and a computer program of a virtual execution environment. In one aspect thereof a data processor includes a read-only storage medium and a virtual machine monitor configured to execute a program in a virtual container. Prior to execution of the application a set of application components accessed during a phase change are recorded in the read-only storage medium in a manner predetermined to minimize the time needed to retrieve the set of components. At the occurrence of the phase change, or prior to the occurrence of a phase change if the files are prefetched, the virtual machine monitor retrieves the components from the read-only storage medium. In a further aspect thereof there is provided a packager of an application to be executed in a virtualization environment by a virtual machine monitor.

Abstract: Disclosed is a method, apparatus and a computer program of a virtual execution environment. In one aspect thereof a data processor includes a disk-based storage system and a virtual machine monitor configured to execute a program in a virtual container. The virtual machine monitor is responsive, prior to execution of the application, to record a set of files accessed during a phase change in the disk-based storage system in a manner predetermined to minimize the time needed to retrieve the set of files. The virtual machine monitor is further responsive, at the occurrence of the phase change, or prior to the occurrence of a phase change if the files are prefetched, to retrieve the files from the disk-based storage system.

Abstract: A method for performing software operations on virtual machine images, includes: receiving a virtual machine image that includes a mapping from a first file name to first file content; reformatting the virtual machine image by: creating a store that contains the first file content and that associates a content descriptor with the first file content, wherein the first file content can be reconstructed by using the content descriptor; and decoupling the mapping by creating an image manifest that maps the first file name to the content descriptor; and performing a software operation on the virtual machine image using the reformatted virtual machine image.

Abstract: A method for creating a virtual machine image, includes: storing a first image manifest for a first virtual machine image, the first image manifest including a mapping from file names of the first virtual machine image to content descriptors; storing a second image manifest for a second virtual machine image, the second image manifest including a mapping from file names of the second virtual machine image to content descriptors; creating a first overlay mapping by: placing a file name and its content descriptor both from the second image manifest in the first overlay mapping; and placing a file name and its content descriptor both from the first image manifest in the first overlay mapping if the file name and its content descriptor are not mapped in the second image manifest; and constructing a third virtual machine image having an image manifest whose mapping is the first overlay mapping.

Abstract: A method for performing software operations on virtual machine images, includes: receiving a first virtual machine image that includes a mapping from a first file name to first file content; reformatting the first virtual machine image by: creating a unique ID for the first file content; and decoupling the mapping of the first virtual machine image by creating an image manifest that maps the first file name to the unique ID, and creating a store that contains the first file content and that maps the unique ID to the first file content; and performing a software operation on the first virtual machine image using the reformatted first virtual machine image.

Abstract: A method for performing software operations on virtual machine images, includes: receiving a virtual machine image that includes data; reclassifying the data into a plurality of parts; and performing a software operation on one of the parts, wherein the software operation is performed without running a virtual machine.

Abstract: An information processing system includes a preparation machine with an installed image; an execution machine on which the installed image is virtually installed; and a virtualizer for virtualizing the installed image on the execution machine to produce a virtually installed image by using a hierarchy of selective virtualizers, wherein the virtualizing is selective such that not all operations of the executing software of the installed image at any particular level are virtualized.

Abstract: A method for executing on a first computer an application having an installed image prepared on a second computer, wherein the installed image is virtually installed on the first computer, is disclosed. The method includes emulating on the first computer a native environment of the second computer. The method further includes detecting an operation of the application upon data, wherein the operation requires an operation on data located on the first computer, and wherein a copy of the data is located in the virtually installed image. The method further includes directing the operation of the application to operate on the data located in the virtually installed image.

Abstract: A method is provided for creating a virtual machine image. According to the method, at least one application is provided on a computer system. After the application is provided on the computer system, at least one optimization of the application is performed based on a runtime environment of the application to produce an optimized application, and the optimized application and at least a portion of the runtime environment are packaged in a virtual machine image. In one embodiment, the computer system is a virtual machine. Also provided is a system for creating a virtual machine image.

Abstract: A novel method is disclosed for capturing an installed state of a conventional application and converting the captured state into a virtual application. The novel method starts with a bare machine in a known state, preferably soon after the OS was installed. Installation scripts are used to install one or more software applications along with required components and dependencies. Other artifacts can be added and configured such as files, trees, directories, entries, data, values, among others. These also may include updates to various system databases, such as the Windows registry in which certain metadata is stored. The installed applications are tested and verified to work as desired. Undesired artifacts can be deleted manually or removed by the OS. The state of the virtual machine with the installed applications is captured. The installed applications can be tested on the frozen virtual machine.

Abstract: Disclosed is a method, computer program product and a server unit of a virtual execution environment having at least one client. The server unit includes a network interface for conducting bidirectional communications with the at least one client and a control unit configured to determine, for individual ones of positions in a virtualized execution of an application, those components that are required at each position; to establish a pseudo-distance between the positions in the virtualized execution of the application; and to identify components that are candidates for prefetching as those components required at one or more positions that are proximate to a current position. The pseudo-distance between positions is indicative of an urgency of prefetching candidate components for regulating an amount of resources devoted to the prefetching of components.

Abstract: A method for updating an application on a host system includes steps or acts of: installing an application on the host system; installing a virtual machine monitor on the host system, installing a first virtual container on the host system, wherein the first virtual container comprises at least one update to the installed application; and instantiating the first virtual container under the virtual machine monitor in a mode wherein the host system can be accessed but not modified and wherein instantiating the first virtual container includes updating the installed application in the first virtual computer and running the updated application in the first virtual container. The method may also include a step of confirming that the updated application runs properly. Optionally, the virtual container may be devirtualized.

Abstract: Disclosed is a method, apparatus and a computer program of a virtual execution environment. In one aspect thereof a data processor includes a disk-based storage system and a virtual machine monitor configured to execute a program in a virtual container. The virtual machine monitor is responsive, prior to execution of the application, to record a set of files accessed during a phase change in the disk-based storage system in a manner predetermined to minimize the time needed to retrieve the set of files. The virtual machine monitor is further responsive, at the occurrence of the phase change, or prior to the occurrence of a phase change if the files are prefetched, to retrieve the files from the disk-based storage system.