Just a week after Citrix announced new products to improve one of the least-loved characteristics of virtual desktop infrastructures, a partner of rival VMware stepped forward with improvements to another.
Citrix’s improvement was to reduce the generic quality of virtual desktop infrastructures that feed thin-client workstations or terminals images of a virtual desktop actually running on a server in the datacenters. The approach is popular with IT departments because it saves money on hardware, licensing, and maintenance, because many users run from the same virtual-desktop image.
While efficient for call centers and other sites in which shift workers share the same hardware, the approach is often unpopular with users, who can’t add their own applications, data and customizations to make their workspaces efficient for them as well as for IT. Last week Citrix tried to lessen the pain with a personalization feature called Personal vDisk to its XenClient and XenServer Virtual Desktop Infrastructure (VDI) packages, which would allow users to use a server-based OS with apps and data installed on the hardware they actually use.
Inability to customize a work environment is a traditional complaint about hosted virtual desktops, but the performance of graphical elements has always been a close second. Improvements in the graphics protocols both Citrix and VMware use to send display information to thin clients and return mouse-movements, button-clicks and other graphical operations commands to the OS on the server have brought them almost up to par, though VMware’s PCoIP is slightly better over slow networks than Citrix’ HDX, according to a comparative review in Network World earlier this month.
Even when clients are connected via encrypted SSL links or virtual private networks, the graphical performance of VMware’s VDI was “very, very good,” because the graphics protocol—PC over IP (PCoIP) from application-acceleration developer Teradici—was installed on the client along with some caching capabilities that allow some graphics to execute locally.
Teradici developed PCoIP for use with zero-client devices, but has expanded its implementation along with new-product developments from VMware to allow it to be used in several different configurations of host and client.
Teradici and VMware boost their graphics performance higher by shifting much of the work of rendering graphics onto a server-offload card, first released a year ago, called the Teradici PCoIP Hardware Accelerator (APEX), which contains a graphical processing unit and caching abilities that can reduce spikes in demand on the CPU by 50 percent and conserve enough processing resources from the server to let it run 20 percent more clients.
“After virtualizing the desktops in all of our classes and computer labs, we noticed issues with performance and quality when running graphic intensive workloads,” according to a statement in the product release from Teradici customer Mahesh Neelakanta, director of IT, College of Engineering and Computer Science, Florida Atlantic University. Using Teradici’s “PCoIP Hardware Accelerator, we can now ensure a high-performance user experience without overprovisioning our server– even in peak workloads.”
The newest version of APEX is an upgrade in the drivers to version 2.23, which according to Teradici manages bandwidth so much more efficiently than earlier versions that it can reduce bandwidth use by half in a VMware Horizon View networks. In the year since it first shipped, 25 percent of VMware Horizon View VDI customers have also installed APEX offload cards.