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BP1018 Sizing and Best Practices for Citrix XenDesktop with Dell EqualLogic Storage 20
Figure 7 Total IOPS on PS6510E array hosting CIFS Share – 1270 virtual desktops
As shown in Figure 7, the total IOPS requirement on the CIFS share was not significant. Redirecting
user profiles and shares helped to reduce the IOPS requirement on the main PS6010XVS array used for
storing and streaming desktop images along with the desktop write caches. It also allows better
manageability of the virtual desktops in a VDI environment.
The IOPS requirement did not vary much for vDisk and CIFS share for the different test scenarios. But
the IOPS on write cache varied significantly for each test scenario and detailed analysis of write cache
IOPS is explained in the following sections.
5.4 Task worker – 100% Pre-boot and login storm
The key observations and findings from the 100% Pre-boot test scenario are analyzed in this section.
5.4.1 Storage layer: EqualLogic array performance
To support 630 virtual desktops, we used eight blade M610 servers and hosted 80 VMs on each blade
server. A single PS6010XVS array was used to host the vDisk and write cache of all the virtual desktops.
Four volumes, each with 500 GB of capacity, were dedicated for allocating write cache for virtual
desktops. Each of the volumes was presented to the ESXi server as an individual datastore. Each of
these volumes hosted the write cache for around 160 virtual desktops. Each virtual desktop was
configured with 1 GB of RAM and 2 GB of write cache. Within a desktop VM, the write cache was
mounted as a 2 GB virtual hard drive (vmdk).