Do Azure App Service Plan slots share CPU/memory?

Question

In a Azure App Service Plan, one can have several slots in addition to the production one.

Do they share resources?

For example, do they each share the same CPU resource or have their own?

In other words, can one slot impact another if it consumes too much (including the production slot)?

Where is this officially documented?

Answer 1

Yes, all deployment slots share resources within the App Service Plan.

Answer 2

As per the official docs,

In App Service, an app runs in an App Service plan. An App Service plan defines a set of compute resources for a web app to run. These compute resources are analogous to the server farm in conventional web hosting.

When you create an App Service plan in a certain region (for example, West Europe), a set of compute resources is created for that plan in that region. Whatever apps you put into this App Service plan run on these compute resources as defined by your App Service plan

For answering your question which is mostly depends on the pricing tier which you have chosen

• Shared compute: Free and Shared, the two base tiers, runs an app on the same Azure VM as other App Service apps, including apps of other customers. These tiers allocate CPU quotas to each app that runs on the shared resources, and the resources cannot scale out.
• Dedicated compute: The Basic, Standard, Premium, and PremiumV2 tiers run apps on dedicated Azure VMs. Only apps in the same App Service plan share the same compute resources. The higher the tier, the more VM instances are available to you for scale-out.
• Isolated: This tier runs dedicated Azure VMs on dedicated Azure Virtual Networks, which provides network isolation on top of compute isolation to your apps. It provides the maximum scale-out capabilities.
• Consumption: This tier is only available to function apps. It scales the functions dynamically depending on workload. For more information, see Azure Functions hosting plans comparison.

For the slot settings as well, it will share all the resources from the App Service Plan