Desktop Virtualization (iii) persistent vs NONP

In the second type and case of desktop virtualization, we explored two architectures for desktop virtualization, hostedvirtual Desktop (VDI), and published Desktop/app. In this article, we analyze the two desktop types of VDI in depth, Persistent and nonpersistent.

One definition:

Persistent Desktop: Typically, each user is assigned a proprietary virtual desktop. User data and personal settings are saved in the virtual machine.

Non Persistent Desktop: a virtual machine is usually selected from within a virtual desktop pool and randomly assigned to the user. User data and personal settings are not saved. Restore to the original initial state after each landing.

The evolution of the second implementation technology

Early-linked Clone

Early in the advent of VDI technology, storage costs were high. Let's put aside de-duplication,compression and other low-level storage optimization technology, assuming that each desktop OS requires 40G, then the 1000 available storage space required for the desktop is 1000*40g=40t.

Is there any way to reduce the cost of storage?

See more highlights of this column: http://www.bianceng.cnhttp://www.bianceng.cn/Servers/virtualization/

The linked clone technology then appears, which allows all virtual desktops to share a master Image, and all operating system-related reads are obtained from this masterimage. Then assign a deltadisk to each virtual desktop, and all writes are recorded to this deltadisk. This saves a lot of storage. But note that as more and more writes are being done, the Deltadisk will occupy more and more space, and in the end will even occupy the same space as masterimage. Then what? Refreshes the virtual desktop. The refreshed Deltadisk will revert to its original size. In the case of nonpersistent, it is acceptable to refresh frequently, because there is no user's data and personality settings on disk nonpersisent desktop. However, if you refresh Persistentdesktop, you must have a plan for how to manage and restore the user's data and personality settings.