5.2

Table Of Contents
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Schedule antivirus and software updates to run at nonpeak hours, when few users are likely to be logged
in.
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Stagger or randomize when updates occur.
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Use an antivirus product that is compatible with the VMware vShield API. For example, this API has been
integrated into VMware vCloud
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Networking and Security 5.1.
As an informal initial sizing approach, to start, assume that each virtual machine requires 1/8 to 1/10 of a CPU
core as the minimum guaranteed compute power. That is, plan a pilot that uses 8 to 10 virtual machines per
core. For example, if you assume 8 virtual machines per core and have a 2-socket 8-core ESX/ESXi host, you
can host 128 virtual machines on the server during the pilot. Monitor the overall CPU usage on the host during
this period and ensure that it rarely exceeds a safety margin such as 80 percent to give enough headroom for
spikes.
Choosing the Appropriate System Disk Size
When allocating disk space, provide only enough space for the operating system, applications, and additional
content that users might install or generate. Usually this amount is smaller than the size of the disk that is
included on a physical PC.
Because datacenter disk space usually costs more per gigabyte than desktop or laptop disk space in a traditional
PC deployment, optimize the operating system image size. The following suggestions might help optimize
image size:
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Remove unnecessary files. For example, reduce the quotas on temporary Internet files.
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Turn off Windows services such as the indexer service, the defragmenter service, and restore points. For
details, see the topics "Optimize Windows Guest Operating System Performance," "Optimize Windows 7
Guest Operating System Performance," and "Overview of Windows 7 Services and Tasks That Cause
Linked-Clone Growth," in the VMware vSphere Administration documentation.
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Choose a virtual disk size that is sufficient to allow for future growth, but is not unrealistically large.
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Use centralized file shares or a View Composer persistent disk for user-generated content and user-
installed applications.
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If you are using vSphere 5.1 or later, enable space reclamation for vCenter Server and for the linked-clone
desktop pools.
If View desktops use the space-efficient disk format available with vSphere 5.1 or later, stale or deleted
data within a guest operating system is automatically reclaimed with a wipe and shrink process.
The amount of storage space required must take into account the following files for each virtual desktop:
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The ESX/ESXi suspend file is equivalent to the amount of RAM allocated to the virtual machine.
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By default, the Windows page file is equivalent to 150 percent of RAM.
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Log files can take up as much as 100MB for each virtual machine.
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The virtual disk, or .vmdk file, must accommodate the operating system, applications, and future
applications and software updates. The virtual disk must also accommodate local user data and user-
installed applications if they are located on the virtual desktop rather than on file shares.
If you use View Composer, the .vmdk files grow over time, but you can control the amount of growth by
scheduling View Composer refresh operations, setting a storage over-commit policy for View desktop
pools, and redirecting Windows page and temporary files to a separate, nonpersistent disk.
You can also add 15 percent to this estimate to be sure that users do not run out of disk space.
VMware Horizon View Architecture Planning
38 VMware, Inc.