Vdisk

Vdisk

In storage virtualization, virtual disk, or vdisk, is a virtual logical disk or volume to which a host or application performs I/O operations. Generally provided by a storage virtualization device and applicable mainly to Fibre Channel storage area network (FC SAN) infrastructures. Presently, the term "vdisk" is used in HP EVA disk arrays and in IBM SAN Volume Controller.

The disk is classed as virtual due to the way it is mapped to the physical storage capacity it represents. In most virtual storage systems a meta-data mapping table is held which translates the incoming (virtual) disk identifier, and LBA (logical block addressing) to a physical disk identifier and LBA.

The virtualization granularity depends on the implementation. Some virtualized systems simply provide what may be thought of more as disk aggregation and so the granularity is a physical disk itself. True virtualization systems actually break down the physical disks into smaller 'chunks' or extents. This can provide a performance benefit by spreading a single virtual disk across many physical disks - therefore getting more concurrent access than a non-virtualized system.


Wikimedia Foundation. 2010.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • VDISK — comp. abbr. Virtual Disk …   United dictionary of abbreviations and acronyms

  • Storage virtualization — refers to the process of abstracting logical storage from physical storage. The term is today used to describe this abstraction at any layer in the storage software and hardware stack.Key conceptsAddress space remappingVirtualization of storage… …   Wikipedia

  • Enterprise Virtual Array — Das HP StorageWorks Enterprise Virtual Array, kurz EVA, erschien 2001 und ist seitdem das einzige voll virtualisierte Storagesystem auf dem Markt. Das System wurde von DEC entwickelt, von Compaq übernommen und im Zuge der Übernahme durch Hewlett… …   Deutsch Wikipedia

  • IBM SAN Volume Controller — In computer data storage, the IBM SAN Volume Controller (SVC) is a block storage virtualization appliance. SVC implements an indirection, or virtualization , layer in a Fibre Channel storage area network (FC SAN). Architecture SVC is always… …   Wikipedia

  • Logical disk — A logical disk is a device that provides an area of usable storage capacity on one or more physical disk drive components in a computer system. Other terms that are used to mean the same thing are partition, logical volume, and in some cases a… …   Wikipedia

  • diskpart — A component of Microsoft Windows Details Included with Windows NT Replaces fdisk In computing, diskpart is a command line hard disk partitioning utility included in versions of the Windows N …   Wikipedia

  • DOS Protected Mode Services — (DPMS) is a set of extended DOS memory management services to allow DPMS enabled DOS drivers to load and execute in extended memory and protected mode. Not being a DOS extender by itself, DPMS is a minimal set of extended DOS memory management… …   Wikipedia

  • Liste des drivers MS-DOS — Il existe principalement trois drivers sous MS DOS ANSI.SYS : permet l interprétation des caractères d échappement DRIVER.SYS : permet de configurer des lecteurs de disquettes ou de bandes exotiques RAMDRIVE.SYS (aussi appelé… …   Wikipédia en Français

  • ramdrive —   (ramdrive.sys, vdisk.sys), Gerätetreiber des Betriebssystems DOS, der es erlaubt, einen Teil des Arbeitsspeichers wie eine Festplatte zu benutzen. Er steht auch unter einigen älteren Windows Versionen zur Verfügung.   Der Befehl »ramdrive« legt …   Universal-Lexikon

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”