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Table Of Contents
Time Required for Recomposing a Pool
You can use a recompose operation to provide operating system patches, install or update applications, or
modify the desktop hardware settings of virtual machines in a pool. Before recomposing a pool, you take a
snapshot of a virtual machine that has new configuration. The recompose operation uses that snapshot to
update all virtual machines in the pool.
In a test setup of 5 pools of 2,000 virtual machines in each pool, a recompose of one pool of 2,000 virtual
machines took 6 hours and 40 minutes. All virtual machines were powered on and available before the
recompose operation began.
Time Required for Refreshing a Pool
Because disks grow over time, you can conserve disk space by refreshing a desktop to its original state when
users log off, or you can set a schedule for periodically refreshing desktops. For example, you can schedule
desktops to refresh daily, weekly, or monthly.
In a test setup of 5 pools of 2,000 virtual machines in each pool, a refresh of one pool of 2,000 virtual
machines took 2 hours and 40 minutes. All virtual machines were powered on and available before the
refresh operation began.
Time Required for Rebalancing a Pool
A desktop rebalance operation evenly redistributes linked-clone desktops among available logical drives. A
rebalance operation saves storage space on overloaded drives and ensures that no drives are underused.
You can also use a rebalance operation to migrate all virtual machines in a desktop pool to or from a Virtual
SAN datastore.
In a test pod that contained 5 pools of 2,000 virtual machines in each pool, 2 datastores were added to the
pod for one test. For another test, 2 datastores were removed from the pod. After the datastores were added
or removed, a rebalance operation was performed on one of the pools. A rebalance of one pool of 2,000
virtual machines took 9 hours. All virtual machines were powered on and available before the rebalance
operation began.
WAN Support and PCoIP
For wide-area networks (WANs), you must consider bandwidth constraints and latency issues. The PCoIP
display protocol provided by VMware adapts to varying latency and bandwidth conditions.
If you use the RDP display protocol, you must have a WAN optimization product to accelerate applications
for users in branch offices or small offices. With PCoIP, many WAN optimization techniques are built into
the base protocol.
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WAN optimization is valuable for TCP-based protocols such as RDP because these protocols require
many handshakes between client and server. The latency of these handshakes can be quite large. WAN
accelerators spoof replies to handshakes so that the latency of the network is hidden from the protocol.
Because PCoIP is UDP-based, this form of WAN acceleration is unnecessary.
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WAN accelerators also compress network traffic between client and server, but this compression is
usually limited to 2:1 compression ratios. PCoIP is able to provide compression ratios of up to 100:1 for
images and audio.
For information about the controls introduced with View 5 that you can use to adjust the way PCoIP
consumes bandwidth, see “Optimization Controls Available with PCoIP,” on page 61.
Chapter 4 Architecture Design Elements and Planning Guidelines for Remote Desktop Deployments
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