The difference between “Always-On” and “On-Demand”
Choose between Always-On and On-Demand fleets to best meet the needs of your students, faculty, staff, and your institutional priorities. Always-On fleets provide immediate access to resources and require a number of machines to be in a running state even if no users are connected. This is recommended when your users need high availability and instant access to applications. On-Demand fleets begin when a user connects to an instance within the fleet, similar to your laptop coming out of hibernation. This is best when your users can wait up to 2 minutes to start applications and for streaming applications that have sporadic use.
|User session start||Up to 2 minutes||Instant on|
|Optimized for||Up to 2 minutes||Instant availability of apps|
|Use cases||Cost savings are critical||Need for instant availability|
These configuration choices directly impact Amazon Web Services (AWS) billing. Always-On provides instant access and in turn requires paying full hourly usage prices, based on the number of instances in the pool whether or not the instance is used. On-Demand provides a slightly delayed access while paying a significantly smaller fee for the standby instance; the full hourly usage fee is only incurred when a user logs in. By default, Propeller utilizes the On-Demand configuration to support your cost-savings.
Sample AWS Pricing*
|Number of instances||5||5|
|Instance configuration||4vCPU / 30.5 GB of Memory||4vCPU / 30.5 GB of Memory|
|Cost per idle hour||.02||--|
|Cost per running hour||.50||.50|
|Usage hour per instance per month||10||720|
|Total cost per month||$91.20||$1,800|
* AWS list pricing for AppStream 2.0, all costs are approximate.