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Sizing and Best Practices for Deploying VMware View 4.5
on VMware vSphere 4.1 with Dell EqualLogic Storage
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users to have their desktop and application settings follow them between different virtual desktops.
Folders like
Desktop , Documents , Pictures , Music , Videos , Favorites , Contacts , Downloads and Links
should be redirected to a user’s home directory in a network file share. By following these practices,
login speeds will improve and a reset of user’s profile will not cause document data loss.
Anti-Virus (AV) Optimizations
A VMware View non-persistent desktop can resume its original state with refresh on logoff or reboot,
so On Access Scanning (OAS), which is typically enabled for inbound (write operations) and outbound
(read operations) should be sufficient. For persistent desktops, On Demand Scanning (ODS) can also
be included, but ODS events should be staggered or randomized to avoid an anti-virus scan I/O storm.
Additional AV best practices include:
• Install a virus scanner. You should not need to install any extra packages provided by the virus
scanner vendor other than the core virus scanning features.
• Include the Network Access Control (NAC) management agent if necessary.
• Use random or staggered scan scheduling.
• Configure scanning exclusion lists to exclude files like
pagefile.sys , *.pst , spool , database and
encrypted files.
Application Delivery Considerations
For VDI environments, you should categorize applications by usage, and leverage application
virtualization as appropriate. For example, the set of applications needed for all users (Microsoft Office,
anti-virus, etc.) should be included the base image. Second and third tier applications could be
delivered via application virtualization.
Boot Storm Considerations
Boot storms can have a large performance impact in a VDI environment as simultaneous booting of a
large number of VMs create a huge IOPS load on the underlying storage systems. To avoid this,
organizations deploying VDI solutions should pre-boot the environment by starting the required
number of VMs well ahead of the time when the first set of users arrives at the beginning of a workday.
With technologies such as hardware-assisted locking in VAAI and automatic workload tiering available
in PS6000XVS, organizations can also pre-boot a certain percentage of the VMs ahead of the time and
then turn on the rest of the VMs on an on-demand basis without affecting performance. This strategy
will lead to lower power consumption and hence improved TCO.
Login/Logoff Storm Considerations
Login and Logoff storms are unavoidable as they depend solely on user arrival and departure times.
Our test results show that it is very important to consider the performance impact of login/logoff
storms, especially when using non-persistent desktops. The VDI infrastructure (and the underlying
Note: See the following VMware View Technical Note for more information:
Anti-Virus
Deployment for VMware View
 http://www.vmware.com/files/pdf/VMware-View-AntiVirusDeployment-WP-en.pdf