Why do companies choose either persistent or non-persistent VDI?

Virtual desktop infrastructure (VDI) services provide companies with an alternative for setting up multiple workstations or computers. They provide virtualized instances of an interface based on a particular operating system. So there are different ways to set this up – two different ways involve either persistent or non-persistent VDI service.

With persistent VDI, each individual workstation or node gets its own fully supported desktop. This way, individual users of these machines can customize and personalize their settings – just as if they were using an operating system physically installed in that one individual computer. With non-persistent VDI, companies get something different: desktops on multiple machines are essentially "cloned" and operated independently of one another, but they work off of the same template, so some forms of customization are not possible. Typically, non-persistent VDI also holds shared files in a shared repository, while a persistent VDI service will display stored files as resident on a particular user workstation.

Companies choose either persistent or non-persistent VDI for various reasons. Most of the trade-offs involve cost versus functionality – persistent VDI is much better for a set of permanent users who will be accessing these machines on an ongoing basis, but on the other hand, it tends to cost more. That's partly because persistent VDI requires more sophisticated storage and more allocated memory than non-persistent VDI.

Companies have to decide whether individual computers supported by a virtual desktop infrastructure service will need to act like individual, standalone machines personalized to assigned users, or not. For example, a set of computers using a VDI system for public access in a library, university or hospital may really not need persistent VDI because there is no long-term assigned user. However, a company that has full-time staffers assigned to different machines may choose persistent VDI, so that even though there is a single service providing virtual operating system interfaces to each computer, each of those computers still looks and acts as though it has its own resident internal operating system.