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There are different schools of thought on sizing the compute layer of the design. The
first is the scale up approach, which uses fewer large hosts to provide resources, while
the scale out approach uses more small hosts to provide resources. The preferred
method is somewhere in between the two approaches, one that utilizes 2 socket hosts
and makes them as dense as possible without violating the consolidation ratios set as
part of the design. This eBook is focused on helping size the compute resources for
the VDI workload.
There are three primary calculations that one will be focused on when sizing the compute
resources in the design. They are the amount of physical memory in each host, the
amount of CPU clock speed and the number of CPU cores and the CPU ratio for them.
Physical memory
First and foremost, one should never overcommit memory in a VDI design. Violating this
rule has very little value and will only lead to performance issues in the environment.
CPU clock speed calculation
The CPU clock speed calculation depends heavily on the details gathered in the previous
desktop assessment. Reports from the assessment will provide the amount of CPU
that user sessions used on average and peak. One will use those details along with the
memory details from the assessment to make the calculations.
Compute Sizing
