Tuning Virtual Desktops for Video Playback

Several clients, especially in the academia, require decent playback of streaming video. For schools, course material is starting to be delivered as an interactive online learning subscription to provide online skill assessments, supplement curriculum instructions, and provide instructional videos to bolster learning skills. VMware Horizon View is tuned for optimal video performance over network links that have up to 150 ms of latency. Before you invest in hardware, there are a few settings you can perform to try and help video performance. If you are running your VMware View environment on a local area network, we can tune PCoIP to improve streaming video.

For virtual desktops using VMXnet3 NICs, you can significantly improve the peak video playback performance of the View desktop by simply setting the following registry setting to the Microsoft recommended value:



HKLM\System\CurrentControlSet\Services\Afd\Parameters
REG_DWORD: FastSendDatagramThreshold 1500

Additionally, creating the following registry keys (which can be applied via GPO) for Max Link Rate and Frame Rate will increase video performance:

HKLM\Software\Policies\Teradici\PCoIP\pcoip_admin
REG_DWORD: pcoip.max_link_rate 900000
REG_DWORD: pcoip.maximum_frame_rate 120

The Max Link Rate entry tells PCoIP how much bandwidth can be consumed. Based on the View 5 guide, the default is 90,000 Kb which is just short of a 100Mb connection. If you are using 1Gb connections, you can set this value to 900,000 Kb which is slightly under the 1Gb connection.

The Frame Rate, which is defaulted at 30, can be adjusted to its maximum of 120.

After adjusting these settings, restart the virtual machines or recompose your pool. This will have an impact on the amount of network bandwidth consumed, but it should improve video performance.

For more information on optimizing PCoIP, see Andre Leibovici's post Optimising PCoIP Display and Imaging.