The way System Engineers approach VDI Performance Tuning may have to change with Windows 11. I’m not so much talking about the techniques as the thinking around measuring performance. While this is early on, and Windows 11 hasn’t yet been released – a video from September 8th 2021 from Microsoft had some interesting points. Steve Dispense, VP of Enterprise Management at Microsoft had some interesting things to say about the new operating system ‘under the hood’.
Windows 11 Thinks of Endpoints First
Okay – they didn’t say this outright, but it is pretty clear from the way things are demonstrated that things like VDI are kind of an afterthought. Microsoft is far more concerned with endpoints and I can’t blame them. So a lot of the things that Microsoft is doing I think will have some pretty obvious benefits for your ‘average’ laptop. I say average with a bit of sarcasm since the minimum requirements will be an Intel 8th gen or better (or AMD Ryzen 2000 and above). As someone who invested in a hefty-at-the-time Dell Precision with a 7th Gen i7 and a TPM 2.x chip it is frustrating to be so close yet just that far away. As a matter of fact, I don’t have a single bit of hardware that will be compatible which is immensely frustrating. For me, especially since I have less than a year of wear on my custom-built Threadripper 2970 system… but I digress.
The security and management features I think will be worth it in terms of remote safety, given the current hybrid/work-from-home climate is likely not going anywhere for a few years at this point. Companies need to support endpoints, and better management is always a better idea. Now, in my opinion, the best endpoint is still one you don’t have to manage. This is the power of solutions like Citrix and IGEL working together to make all of this a moo point (you know, like a cow… who cares?). Moot or not, the reality is that to this day the vast majority of teams are still deploying these legacy-style devices and refreshing them to keep users and IT teams happy. Microsoft is doing the right thing, in my opinion, by essentially hitting the reset button and doing something new rather than just doing yet another refresh/patch to Windows 10.
A long-standing frustration of mine has been system services in both Windows 10 and Server 2016/2019 that run at normal or sometimes above normal priority settings. Further frustrating is a lack of granularity with priorities – Idle, Below Normal, Normal, Above Normal, and High do a fairly good job but there is no reason we couldn’t have additional priorities. For those that don’t know, think of the thousands of threads going on in your CPU as being part of an execution queue. While more threads helps because you have more queues, so many apps are now multi-threaded that once again the CPU scheduler is being tasked with choosing who goes first. The problem is when everyone is Normal – no one is.
Windows 11 is apparently changing that by favoring any foreground app with an Above Normal status. This is potentially a step forward given how thread-heavy Windows has become without any other apps running. The problem typically, however, is balancing this. The vast majority of even modern apps do not manage themselves well. We will see how that goes. Dispensa did note that the end result of this is that you may see HIGHER CPU utilization – something we’ll get into in a moment when talking VDI.
The key is how Microsoft is deciding what gets the most attention by the CPU scheduler, and in my opinion, it is a game-changer – the app that is in front! In other words, as near as I can tell – say I’m running a process (let’s say Handbrake) and it is humming along, but I decide to open a document. When I open the document, Word becomes the higher priority and Handbrake takes a backseat, consuming only what resources are left after Word is done. Granted, the only way this really works in real life is when one thing does not depend on the other – but that is so rare at this point it is barely worth considering, especially on your average endpoint.
What remains to be seen is what is considered Foreground. For example, let's say I’m running all four of my monitors and am taking advantage of the new snap configurations. Instead of my normal eight programs all running in the ‘foreground’ I have, say, 18. Perhaps one of those is Zoom and I’m presenting my screen or running a webinar… or streaming ThriveCast. How will it decide what gets the true priority? Location of the mouse maybe? I can see that becoming a challenge if there are only the aforementioned priority levels to manage. If I click on the screen I’m presenting and it takes priority over Zoom – Zoom may not be able to get the resources it needs if there are now 16 other programs on the sort-of-forefront area vying for the CPUs attention.
User Perception is going to be key for Windows 11
On the whole – I think user perception is the important factor. This is what I’ve been trying to get System Engineers to think more about for the past five or so years! On the whole, even the small little changes in what matters most to the user will, I think, be received very positively. Given that this even exceeds most third-party capabilities we have today, this subtle little change could be the most impactful user experience play in Microsoft’s history… and few will realize it.
That is, assuming it works and the OS can properly determine what ‘foreground’ really means and how to manage the rest. We will see what tricks Microsoft has up the Windows 11 performance sleeve!
In other words…
Perhaps the biggest takeaway for System Administrators and even Systems Engineers – you can no longer look at ‘high CPU' as the ‘smoking gun' for degraded user experience. This will present a learning curve – but I believe in you. You can do it.
While what was mentioned in the video was not much more than managing Edge tabs, I think there’s more going on. We’ll go into more of this soon because I think this is a bigger deal for VDI, especially those that haven’t discovered the magic of Citrix Environment Management. Steve mentioned almost inaudibly that the thresholds here will be GPO configurable. Hello? That is HUGE!
Resume from Sleep
Yawn. I’m sure there are people in the world that care about this. I’m not sure I really know any who do care… But – once again, Microsoft is managing threads in such a way to make resume from sleep easier and less burdensome on the battery (in other words, there may finally be a reason not to just straight up hibernate your laptop or just power it off completely like I do). Sleep in Windows 10 was, let us be honest, a bit of a joke. Most of the time my laptop would wake up without being prompted, or the overly powerful i7 + Quadro would kill the battery in almost the same amount of time as being awake.
Will this change anything for me? Time will tell. If anyone wants to buy me a new Surface to know for sure, please let me know. I’m sure I’ll be thrilled about the faster Hello for Business time to desktop… surely (ahem – work from home… we aren’t going to care, Microsoft…).
VDI Is Second Class Again… or is it?
Again – I always want People in IT to think of PEOPLE first. The user experience is paramount. How this all plays out in the real world has yet to be seen. For example, my friends at G0-EUC did some initial testing and found that Windows 11 consumes more resources – though they note correctly that the amount of resources is less than the percentage jumps we saw from Windows 7 to 10 (ignoring 8 because it was the Vista of this generation… or perhaps the Windows Me).
What interests me about these kinds of tests is that it is very difficult to measure user perception of experience. As a LoginVSI Technical Advocate, I will tell you that I’m very proud of the fact that this has been central to LoginVSI for some time – in fact, the primary indicator of too much load has been when the user experience degrades. We will see how Windows 11 behaves under synthetic load conditions as compared to real user interaction, but I’m hopeful.
It is like WEM for Everyone
While Citrix Workspace Environment Management (WEM) has been a game-changer for ServerOS workloads and VDI alike the real power has always been in controlling resources via policy. As I mentioned in Chapter 6 of Be A Citrix Hero and demonstrate in the Citrix Hero Program lecture “Quick Wins with WEM” – we should always focus first on the big wins. Well, up until Windows 11 this has always been memory and CPU priority management. The myriad of other things WEM can do are great but from the user perspective, these are what matters.
On-Premises Workloads Beware
I’m going to go ahead and predict this now: If you are among the majority of those still running on-prem workloads, Windows 11 will make it VITALLY important to properly isolate and scale your hypervisors! Some of the features they are demonstrating today in terms of apps being in a default state of a stub and then loaded on the fly are great for space management… but I’m willing to bet right now that this will present challenges in terms of VDI scaling. That is nothing, however, to the CPU utilization we will see with the new structure. Perhaps we will finally stop being afraid of running our hosts at 70%+ CPU and being confident the user experience does not suffer… as long as that ends up being true! VDI has been a challenge in this regard from its beginnings. We will see what effects dynamically loading inbox apps and compressed file states have on scalability. For endpoints – yeah, that’s great and all. But for VDI… I can see challenges ahead – so get those isolated clusters ready!
The good news here is memory management. We may truly be able to go back to VMs with 2 vCPU and 4 GB RAM instead of some of the insane VDI configurations I’ve been seeing lately. ROI may increase dramatically if the memory management features extend past Edge. If not… WEM 😉
Windows 11 and Annual Feature Updates
The insanity may be… well, lessened. Microsoft will only be releasing feature updates annually – though I must note that Pro will still only have 24 months of support and Enterprise will have 36 months. In my experience, most ISVs and IT Teams look more for a five-year support cycle so I still have some questions about if we’ll be seeing any kind of LTSC versions of Windows 11. Given how resistant Microsoft has been – time will tell (and – I may not have all the information… feel free to correct me!).
Do I care about the update process? 40% smaller updates… okay. VDI I don’t think matters for this but perhaps this Cumulative Update process will matter for MEM more than I am seeing because that’s not my day-to-day. I’m interested to see how zero-day threats could be potentially be enabled for VDI in these scenarios. What they didn’t mention is the ability to have no-reboot patching. It is something that was rumored but I’ve yet to see anything about it. That’s the problem with rumors.
Well- there aren’t any yet. Because of my aforementioned hardware ‘challenges,’ I’ve yet to be able to go for Windows 11. I will be trying an Azure VM soon but in my mind, that is hard to get a true experience result. As I’ve hopefully tried to get across in this article – it is ALL ABOUT THE USER EXPERIENCE.
Overall, I’m more excited about Windows 11 than I thought I would be after watching today’s video and I’m looking forward to what else we’ll find!