Category: PVS

Citrix PVS – NTFS vs ReFS 2012R2 vs ReFS 2016

I’ve been doing some work recently around Citrix Provisioning Services, and this has prompted me to investigate what new features are available in version 7.11. One that stood out to me was the support for Microsoft’s Resilient File System (ReFS) on Windows Server 2016. This file system is interesting for those with virtualized environments due to the extra speed enhancements around the use of VHD and VHDX files.

What’s also interesting is that Citrix state the type of performance enhancement that can be expected when using this version:


So… I decided to test this out!

I started with a basic PVS setup of 1 server and 1 client – but times three to give me three farms. The first farm being a 2012R2 Server with the PVS vDisk storage on NTFS, the second being 2012R2 using ReFS, and the third being 2016 using ReFS. All of the client machines captured for the session hosts were 2012R2. All base specifications were identical with 4GB RAM and 1vCPU.

Capture Times:

  • Capture time for NTFS on 2012R2: 8:44
  • Capture time for ReFS on 2012R2: 5:50
  • Capture time for ReFS on 2016: 5:15

Boot Times:

PVS Server Streaming Directory – NTFS on 2012R2:

PVS Server Streaming Directory – ReFS on 2012R2:

PVS Server Streaming Directory – ReFS on 2016:

Testing vDisk Merging:

To test out vDisk merging I created a new maintenance revision and booted the client machines from this:

I then installed a number of applications using Ninite:

Installing these and the associated changes created a file size of around 4.5Gb for the differencing disk.

I then merged the changes to create a new base:

  • NTFS on 2012R2: 12:44
  • ReFS on 2012R2: 4:04
  • ReFS on 2016: 0:14 (yes… less than 15 seconds!)


As you can see – there is a noticeable speed increase when using ReFS on 2016 – in all tests the performance was significantly faster. Capture was around 40% faster. Boot times within my lab environment were almost negligible they were that fast – but ReFS on 2016 had a 3 second lead over ReFS on 2012R2, and 4 seconds on NTFS on 2012R2. Perhaps the most impressive speed increase was the merge operation though – 12:30 faster on ReFS on 2016 than NTFS on 2012R2!

All in all it’s pretty clear what I will be using when implementing PVS from now on….

Book Review – “Inside Citrix – The FlexCast Management Architecture” by Bas van Kaam

Recently I have been reading the excellent “Inside Citrix – The FlexCast Management Architecture” by Bas van Kaam. I wanted to write a quick post up about this book – as it’s well worth a read for anyone working with Citrix Desktop Virtualization products.,204,203,200_.jpg?resize=221%2C340&ssl=1

You can purchase the book here.

What I really like about this book is how thorough the sections are – no area is left untouched. Each element of the FlexCast infrastructure is covered, including the history behind FMA, and an overview of how FMA is different to IMA. As well as thorough details, there is also an excellent troubleshooting section, which goes through various tools and troubleshooting methods, and various cloud services available to assist.

Also, each section has a “Key Takeaways” area at the end, which provides an overview – highlighting the key elements and considerations covered. This is really useful if you are wanting to improve your knowledge in a particular area. Just by reading this book I’ve already uncovered, and filled, gaps in my own knowledge – this for me is the main reason for reading any technical publication.

Overall, for anyone working with Citrix products this book is an excellent read in my opinion – not only useful for improving your knowledge, but also serving as a reference guide when there are decisions to be made.