VDI Calculator v6.5 is Now Available Raising Questions on VDI Market

Wow! What a phenomenal journey this VDI calculator has been through. It all started as an Excel spreadsheet in 2010 and later on evolving into a Flash based app and later into a Java based app. Since June 2013 when I implemented access counters using GoogleAnalytics this calculator has been used over 52,000 times by different sources, with United Stated and UK leading the pack.


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While analyzing the calculator’s usage pattern it is clear that the usage has been declining since mid 2014. Could it be that we have achieved plateau for VDI market? or could be that solution architects have now mastered how to properly size VDI solutions without help of the calculator. It could also be a combination of both, but I think the core reason is a little different and I have written about it before in Are PoC and Pilot no longer required for VDI deployments?.

Quoting my original article.

Since 2011 hyper-convergence has emerged and matured, removing many of the complex aspects required to rollout successful VDI solutions.

The inexistence of dual-controllers like in centralized storage (SAN) completely removed the need to validate storage architectures under full load. The distributed nature of hyper-converged solutions warrants testing a single server under load to be enough to characterize an entire VDI deployment, independent if 100 or 100K users. You will know that for a given user profile you are able to have n users per server.

That also means that there aren’t calculations required for the number and types of disks, RAID groups, LUNS or controller overload in case of failures. Hyper-convergence implements an independent virtual controller per server; and in case of a server component failure only the desktops in that server are affected, not the entire fleet.

Finally, hyper-convergence excels when VDI deployments need to grow, not requiring complex math exercises to calculate storage performance and capacity expansions. Remember, you already know how many users of a given profile the server will support; simply add servers to the existing cluster.


Today I am releasing a new version on my VDI calculator, 6.5.


  • Nutanix Calculation Update – Previous versions of the calculator assumed that all eight cores assigned to the controller VM were in-use, but with the latest releases of Nutanix Based OS this is hardly the case. Commonly only four CPU cores will be in use at any point in time; even during boot storms. This change increases the overall VM consolidation per host achieved on Nutanix platform. If you have previously sized for Nutanix I recommend re-running your configuration and verifying the new result.
  • Default Memory Sharing set to Zero – A recent academic research that leverages Transparent Page Sharing (TPS) to gain unauthorized access to data under certain highly controlled conditions and documents VMware’s precautionary measure of restricting TPS to individual virtual machines by default. The new default TPS is 0, but it can be changed if desired. A warning will be displayed to the user upon default change. http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2080735
  • Advertising is Gone! – Gone is the advertising banners displayed by the calculator.
  • UI Design Changes – The interactive buttons now seat all at the bottom of the calculator where the ads used to be displayed.
  • Acropolis Hypervisor – The plumbing work to support Nutanix Acropolis hypervisor for VDI deployments is complete. With Citrix XenDesktop, Workspot, Systancia and UDS Enterprise supporting their VDI solutions on Acropolis it is time to add Acropolis in the calculator. The next release will provide the support. Read What are the VDI options for Nutanix Acropolis Hypervisor?
  • Few other small bugs have been squashed.



To access the VDI calculator click here.



This article was first published by Andre Leibovici (@andreleibovici) at myvirtualcloud.net.


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