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Dell DVS Simplified Appliance Reference Architecture
storage reduction. Otherwise, each VM would require 100% of the disk space reservation
used by the golden image.
Another significant point is that the vdiManager virtual machine must be installed on each
host machine. This requirement expands the storage necessity by 75 GB per server for the
vdiManager VM as well as an additional amount for swap and other transient activity that
varies based on the number of virtual desktops and memory allocated to each virtual
desktop.
The next important factor when considering storage capacity is the type of local storage
(e.g., SATA or SAS) to utilize for virtual machines. The type of storage must be able to
accommodate the amount of input/output operations per second (i.e., IOPS) that
originate from the virtual machines. Note that each virtual machine may be allocated
differently and therefore must take into account the user profile assigned.
As guidance for the solution, disk IOPS and user profile IOPS were used to calculate the
type of drive needed. The following tables outline the IOPS profile per drive and per user
type, respectively.
Drive Type
IOPS per Drive
7200 RPM SATA Hard Drive
75 IOPS
10k RPM SAS Hard Drive
150 IOPS
User Type
IOPS per User Type
Basic Workload
10 IOPS
Standard Workload
12 IOPS
Premium Workload
15 IOPS
4.2.1
Disk Space Requirement by Workload
Given these listed storage considerations, we can calculate the amount of storage
required to house the 129, 100 and 70 desktop VM configurations for the standard level
system and the 65, 50 and 35 desktop VM configurations for the entry level system. Using
2 golden images that are the same size, it is straight forward to calculate the amount of
storage required:
Standard Configuration
User Type
Storage Type
Space Requirements
Basic Workload
Golden Images
2 x 20GB × 2 Golden Images = 80GB
Virtual Machines
15% × 20 GB × 129 VMs = 387GB
Total Server Capacity
80GB + 387GB + 129GB(Swap) + 75GB
(vdiManager VM) = 671GB per Server
Recommended Buffer Space
10% × 20GB ×129 VMs = 258 GB
Standard
Workload
Golden Images
2 x 25GB × 2 Golden Images = 100GB
Virtual Machines
15% × 25GB × 100 VMs = 375GB