A de-duplication is configured to cache data for access by a plurality of different storage clients, such as virtual machines. A virtual machine may comprise a virtual machine de-duplication module configured to identify data for admission into the de-duplication cache. Data admitted into the de-duplication cache may be accessible by two or more storage clients. Metadata pertaining to the contents of the de-duplication cache may be persisted and/or transferred with respective storage clients such that the storage clients may access the contents of the de-duplication cache after rebooting, being power cycled, and/or being transferred between hosts.

Systems and methods for a de-duplication cache

According to certain aspects, a system includes a client device that includes a virtual machine (VM) executed by a hypervisor, a driver located within the hypervisor, and a data agent. The VM may include a virtual hard disk file and a change block bitmap file. The driver may intercept a first write operation generated by the VM to store data in a first sector, determine an identity of the first sector based on the intercepted write operation, determine an entry in the change block bitmap file that corresponds with the first sector, and modify the entry in the change block bitmap file to indicate that data in the first sector has changed. The data agent may generate an incremental backup of the VM based on the change block bitmap file in response to an instruction from a storage manager, where the incremental backup includes the data in the first sector.

Virtual machine change block tracking

Systems and methods enable a virtual machine, including any applications executing thereon, to quickly start executing and servicing users based on pre-staged data blocks supplied from a backup copy in secondary storage. An enhanced media agent may pre-stage certain backed up data blocks which may be needed to launch the virtual machine, based on predictive analysis pertaining to the virtual machine's operational profile. The enhanced media agent may also pre-stage backed up data blocks for a virtual-machine-file-relocation operation, based on the operation's relocation scheme. Servicing read requests to the virtual machine may take priority over ongoing pre-staging of backed up data. Read requests may be tracked so that the media agent may properly maintain the contents of an associated read cache. Some embodiments of the illustrative storage management system may lack, or may simply not require, the relocation operation, and may operate in a “live mount” configuration.

Efficient live-mount of a backed up virtual machine in a storage management system

The data storage system according to certain aspects can manage the archiving of virtual machines to (and restoring of virtual machines from) secondary storage. The system can determine whether to archive virtual machines based on usage data or information. The usage information may include storage usage, CPU usage, memory usage, network usage, events defined by a virtual machine software or application, etc. The system may archive virtual machines that are determined to have a low level of utilization. For example, a virtual machine can be archived when its usage level falls below a threshold level. The system may create a virtual machine placeholder for an archived virtual machine, which may be a “light” or minimal version of the virtual machine that acts as if it is the actual virtual machine. By using a virtual machine placeholder, a virtual machine may appear to be active and selectable by the user.

Archiving virtual machines in a data storage system

The disclosed systems and methods enable a virtual machine, including any applications executing thereon, to quickly start executing and servicing users based on pre-staged data blocks supplied from a backup copy in secondary storage. Substantially concurrently with the ongoing execution of the virtual machine, a virtual-machine-file-relocation operation may move data blocks originating in the backup copy to a primary storage destination that becomes the virtual machine's primary data store after the relocation operation completes. An enhanced data agent, operating in conjunction with an enhanced media agent in a storage management system, coordinates restoring of the virtual machine and the launch of the relocation operation. The enhanced media agent may pre-stage certain backed up data blocks which may be needed to launch the virtual machine, based on predictive analysis pertaining to the virtual machine's operational profile. The enhanced media agent may also pre-stage backed up data blocks for the relocation operation, based on the operation's relocation scheme. Servicing read requests to the virtual machine may take priority over ongoing pre-staging of backed up data. Read requests may be tracked so that the media agent may properly maintain the contents of an associated read cache. Some embodiments of the illustrative storage management system may lack, or may simply not require, the relocation operation, and may operate in a “live mount” configuration.

Efficiently restoring execution of a backed up virtual machine based on coordination with virtual-machine-file-relocation operations

Embodiments of the invention provide techniques for ensuring that the contents of a non-volatile memory device may be relied upon as accurately reflecting data stored on disk storage across a power transition such as a reboot. For example, some embodiments of the invention provide techniques for determining whether the cache contents and/or or disk contents are modified during a power transition, causing cache contents to no longer accurately reflect data stored in disk storage. Further, some embodiments provide techniques for managing cache metadata during normal ("steady state") operations and across power transitions, ensuring that cache metadata may be efficiently accessed and reliably saved and restored across power transitions.

Managing cache data and metadata

Aspects of the subject matter described herein relate to file system placeholders. In aspects, placeholders may be used by a client to represent remote file system objects. The placeholders may include metadata and may also include none, some, or all of the content of the represented remote file system objects. In response to a request to access content of a file system object represented by a placeholder, a client may obtain needed data from a remote storage system and stream or not stream the data to the requesting application based on whether the requesting application is capable of streaming the data.

Streaming content and placeholders

To ensure that the contents of a non-volatile memory device cache may be relied upon as accurately reflecting data stored on disk storage, it may be determined whether the cache contents and/or disk contents are modified during a power transition, causing cache contents to no longer accurately reflect data stored in disk storage. The cache device may be removable from the computer, and unexpected removal of the cache device may cause cache contents to no longer accurately reflect data stored in disk storage. Cache metadata may be managed during normal operations and across power transitions, ensuring that cache metadata may be efficiently accessed and reliably saved and restored across power transitions. A state of a log used by a file system may be determined prior to and subsequent to reboot of an operating system in order to determine whether data stored on a cache device may be reliably used.

Method and system for ensuring reliability of cache data and metadata subsequent to a reboot

A file access request is received from an application. One or more file types for the file access request are identified, and one or more file hosts supporting files of the identified one or more file types are also identified. A user interface is displayed, the user interface including a hosted area. Within the hosted area, at least one of the one or more file hosts displays a portion of the user interface identifying one or more files of at least one file host that can be selected for retrieval, or one or more locations that can be selected to which the one or more files are saved.

File access with different file hosts

The claimed subject matter provides for systems and/or methods for accessing and/or updating files by a first application in which the first application does not have direct accessibility to said file. In some embodiments, file host applications that are not directly accessible to said first application may be connected to through a file picker extensibility point that enable the first application to acquire files through an operating system user experience. In these various embodiments, the system may provide for one or more of the following functionalities: (1) refreshing content that is controlled by a file host application; (2) updating content that is controlled by a file host application; (3) exporting files from an application to a file host application; (4) a user interface for export operations and file host application intervention and (5) a file host extensibility point provided by the operating system.

David Fields

Papers

Managing cache data and metadata

Streaming content and placeholders

Method and system for ensuring reliability of cache data and metadata subsequent to a reboot

File access with different file hosts

Mechanisms for connecting files between applications