Technical data

Solution Architectural Overview
VMware Horizon View 5.3 and VMware vSphere for up to 2,000 Virtual
Desktops Enabled by Brocade Network Fabrics, EMC VNX, and EMC Next-
Generation Backup
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to some degree. The administrator has the responsibility to monitor
proactively the oversubscription rate such that it does not shift the
bottleneck away from the server and become a burden to the storage
subsystem.
If VMware vSphere runs out of memory for the guest operating systems,
paging will begin to take place, resulting in extra I/O activity going to the
vswap files. If the storage subsystem is sized correctly, occasional spikes
due to vswap activity might not cause performance issues because
transient bursts of load can be absorbed. However, if the memory
oversubscription rate is so high that the storage subsystem is severely
impacted by a continuing overload of vswap activity, more disks will need
to be added—not because of capacity requirement—but due to the
demand of increased performance. The administrator must decide
whether it is more cost effective to add more physical memory to the
server or to increase the amount of storage. With memory modules being
a commodity, it is likely less expensive to choose the former option.
This solution was validated with statically assigned memory and no over-
commitment of memory resources. If memory over-commit is used in a
real-world environment, regularly monitor the system memory utilization
and associated page file I/O activity to ensure that a memory shortfall
does not cause unexpected results.
The solution outlines the minimum needs of the system. If additional
bandwidth is needed, it is important to add capability at both the storage
array and the hypervisor host to meet the requirements. The options for
network connectivity on the server will depend on the type of server. The
storage arrays have a number of included network ports and have the
option to add ports using EMC FLEX I/O modules.
For reference purposes in the validated environment, EMC assumes that
each virtual desktop generates 10 I/Os per second with an average size of
4 KB. This means that each virtual desktop is generating at least 40 KB/s of
traffic on the storage network. For an environment rated for 500 virtual
desktops, this comes out to a minimum of approximately 20 MB/sec. This is
well within the bounds of modern networks. However, this does not
consider other operations. For example, additional bandwidth is needed
for:
 User network traffic
 Virtual desktop migration
 Administrative and management operations
The requirements for each of these will vary depending on how the
environment is being used. It is not practical to provide concrete numbers
in this context. The network described in the solution for each solution
should be sufficient to handle average workloads for the above use cases.
The specific Brocade storage network layer connectivity solution is defined
in Chapter 5.
Network
resources