Abstract: Described is a technology by which a virtual hard disk is able to continue servicing virtual disk I/O (reads and writes) while a meta-operation (e.g., copying, moving, deleting, merging, compressing, defragmenting, cryptographic signing, lifting, dropping, converting, or compacting virtual disk data) is performed on the virtual disk. The servicing of virtual disk I/Os may be coordinated with meta-operation performance, such as by throttling and/or prioritizing the virtual disk I/Os. Also described is performing a meta-operation by manipulating one or more de-duplication data structures.

Abstract: Described is a technology by which a virtual hard disk is maintained between a far (e.g., remote) backing store and a near (e.g., local) backing store, which among other advantages facilitates fast booting of a machine coupled to the virtual hard disk. Read requests are serviced from the near backing store (e.g., a differencing layer) when the data is available thereon, or from the far backing store (e.g., a base layer) when not. The near backing store may be configured with a cache layer that corresponds to the base layer and a write differencing layer that stores writes, or a single differencing layer may be used for both caching read data and for storing write data. A background copy operation may be used to fill the cache until the far backing store data is no longer needed.

Abstract: Described is a technology by which a virtual hard disk is able to continue servicing virtual disk I/O (reads and writes) while a meta-operation (e.g., copying, moving, deleting, merging, compressing, defragmenting, cryptographic signing, lifting, dropping, converting, or compacting virtual disk data) is performed on the virtual disk. The servicing of virtual disk I/Os may be coordinated with meta-operation performance, such as by throttling and/or prioritizing the virtual disk I/Os. Also described is performing a meta-operation by manipulating one or more de-duplication data structures.

Abstract: Described is a technology by which a virtual hard disk is able to continue servicing virtual disk I/O (reads and writes) while a meta-operation (e.g., copying, moving, deleting, merging, compressing, defragmenting, cryptographic signing, lifting, dropping, converting, or compacting virtual disk data) is performed on the virtual disk. The servicing of virtual disk I/Os may be coordinated with meta-operation performance, such as by throttling and/or prioritizing the virtual disk I/Os. Also described is performing a meta-operation by manipulating one or more de-duplication data structures.

Abstract: Described is a technology by which a virtual hard disk is maintained between a far (e.g., remote) backing store and a near (e.g., local) backing store, which among other advantages facilitates fast booting of a machine coupled to the virtual hard disk. Read requests are serviced from the near backing store (e.g., a differencing layer) when the data is available thereon, or from the far backing store (e.g., a base layer) when not. The near backing store may be configured with a cache layer that corresponds to the base layer and a write differencing layer that stores writes, or a single differencing layer may be used for both caching read data and for storing write data. A background copy operation may be used to fill the cache until the far backing store data is no longer needed.

Abstract: Described is a technology by which a virtual hard disk is able to continue servicing virtual disk I/O (reads and writes) while a meta-operation (e.g., copying, moving, deleting, merging, compressing, defragmenting, cryptographic signing, lifting, dropping, converting, or compacting virtual disk data) is performed on the virtual disk. The servicing of virtual disk I/Os may be coordinated with meta-operation performance, such as by throttling and/or prioritizing the virtual disk I/Os. Also described is performing a meta-operation by manipulating one or more de-duplication data structures.

Abstract: The invention comprises an improved Christmas tree stand having a central support hub which has a shaft embedded therein which extends upwardly from an upper portion of the hub. The shaft is adapted to penetrate the base of a tree trunk for supporting the trunk on the hub. At least three leg members extend outwardly from the hub for supporting the hub and the tree engaged by the shaft. A liquid retaining reservoir is provided a top the central support hub for retaining water for nourishing a tree supported by the shaft.