Automated power on of WVD instances in response to user connection attempts.
Given the new authentication and connection process utilised within WVD, it would be extremely useful to offer "Just in time" or "on demand" powering on of Dedicated or Pool WVD desktops in direct response to use login attempts.
This capability, coupled with centralised scheduling (to spin up some or all machines automatically during business hours for example) would hugely simplify the process of optimising the cost of utilising WVD by organisations - and remove significant complexity from the administration process.
Example:- Contoso has 100 designers using dedicated powerful (and costly) WVD GPU enabled desktops. Mostly they work during business hours, but some users work overtime or flexible hours, and so may need to access their desktops outwith the normal working day.
If the WVD platform was able to power on (in response to a connection attempt from the WVD client to a stopped instance) or off (when the user chooses to shut the instance down) then Contoso could save significant costs versus running the instances 24/7, and significantly reduced administrative overhead versus having to manage scheduled jobs or respond re-actively to user requests to access their devices out of hours.
The short delay in the client of perhaps a minute while the instance they have requested is started in response to their connection attempt would be a small price to pay for the convenience and cost saving this feature would bring.
As Microsoft control the proprietary client/API/SDK for the new authentication and connection process used by WVD, implementation of this feature should be relatively painless inclusion.
See our public roadmap for dates. https://www.microsoft.com/en-us/microsoft-365/roadmap?featureid=70198
Pistle Jumbo commented
The PeakServerStartThreshold is the number of user sessions that should be available between each run, not the number of session hosts that should stay running. By design, this script will try to minimize the number of servers running. With Depth-first load balancing WVD would not allocate sessions to a new server until one with active connections hits the max session count. You could keep an extra server running by durring peak by setting the threshold to the max session count +1.