Users will only accept the transition to VDI if the virtual desktops they work with perform at least as well as the physical desktops they were accustomed to.
Matching the performance of physical desktops can be a tall order, however, considering that virtual desktops share network resources.
The value of real-time performance monitoring
One way to mitigate VDI performance issues is with real-time performance monitoring, which allows IT to spot and remediate changing conditions before those conditions cause any noticeable problems. Rapid detection and response are critical to ensure a good end-user experience, but they are not the only steps IT can take.
IT can configure virtual desktops and alter settings to yield optimal virtual desktop performance.
1. Eliminate boot storms
One way to minimize performance problems is to eliminate boot storms, which occur when too many users boot their virtual desktops at the same time, often at the beginning of the workday. IT can prevent boot storms by configuring the virtual desktops to boot automatically just before the workday begins.
2. Avoid overprovisioning
IT can also limit the effects of boot storms by not overprovisioning the virtualization hosts. To do so, IT must ensure that the back-end infrastructure has enough resources to cope with periods of heavy activity.
3. Set a resource limit
Similarly, IT can set a resource limit for individual desktops to prevent one virtual desktop from using too many resources. For example, IT can use Microsoft Storage QoS -- a program that helps manage and monitor virtual machines -- or similar software to prevent any virtual desktop from consuming too much storage IOPS.
4. Don't use roaming profiles
Another step IT can take to reduce logon times and other VDI performance issues is to deploy Microsoft User Experience Virtualization. This tool allows users to keep the same desktop across multiple devices and prevents them from relying on roaming profiles.
Roaming profiles require copying profile elements to Windows as a part of the login process. This process can hinder performance, especially if the profiles are large or multiple users log on simultaneously.
Sharing VDI resources
IT can act within Windows to make VDI perform better. This means tuning the Windows operating system to use resources better, helping overcome some of the constraints associated with using the operating system on virtual desktops.
1. Disable virtual memory
One option is to disable virtual memory use within the virtual desktops. By default, Windows moves memory pages to a disk-based pagefile to conserve RAM. This paging operation consumes storage IOPS, diminishing network performance. IT can safely disable virtual memory if it provisions the desktop with enough RAM.
2. Use a clean operating system deployment image
IT should create clean operating system deployment images. A default Windows installation is full of bloatware and unnecessary processes and services. Uninstalling software, removing unneeded features and disabling unnecessary services can go a long way toward improving virtual desktop performance.
While manually cleaning up a Windows deployment can be tedious, there are tools that can help. One such tool is the Windows 10 Debloater, designed to strip bloatware from a fresh Windows 10 installation.
3. Turn off OS-level visual effects
Turning off OS-level visual effects like transparency and animation can free up resources. Visual effects may consume a small amount of memory and CPU, but reclaiming even a few resources can prevent VDI performance issues in an organization where users share resources.
4. Disable maintenance tasks
The OS runs several automatic maintenance tasks that may be appropriate for physical desktops but are a problem with virtual desktops that IT should consider disabling. Tasks such as hard disk defragmentation and automated deep malware scans can consume a lot of IOPS, causing VDI performance issues, such as network latency, without delivering any significant benefit in return.
In a virtual desktop environment, IT should disable indexing as it can consume a significant amount of CPU and storage IOPS resources. The group policy settings that control tuning and disabling the indexing service are found at Computer Configuration > Administrative Templates > Windows Components > Search.
Use group policy to schedule updates
Regularly installing available updates is an important part of keeping the Windows operating system healthy and secure. However, the update process in a VDI environment generates storage IOPS, which can adversely impact performance. Therefore, it's best to configure Windows to install updates during off-peak hours to minimize the impact of the update process.
IT can set an update schedule by following these steps:
- Open the Group Policy Editor and navigate to Computer Configuration.
- Select Policies.
- Select Administrative Templates.
- Select Windows Components.
- Select Windows Update.
- Locate and double-click a policy setting named Configure Automatic Updates.
- Choose Auto Download and Schedule the Install from the drop-down list.
From there, IT can choose the day and time to install updates. Remember, because updates write to virtual desktops, it is important to ensure they're powered on at the designated install time.
Turn off OS power-saving features
One last setting to consider is Windows' High Performance power plan. This may sound counter-intuitive, but Windows consumes various hardware resources when it goes into and comes out of hibernation. IT can reduce VDI performance issues by turning off any OS power-saving features.
The easiest way to accomplish this is to use group policy to implement the preferred power management settings. The various power management settings are available at Computer Configuration > Administrative Templates > System > Power Management.