SharePoint: SharePoint Online search query volume limits when using app-only authentication

Originally posted by Microsoft Oct 2, 2021 SharePoint Online 0 Comments

When using the SharePoint Online search APIs with app-only authentication where the app implements the Sites.Real.All permissions level or greater, the app is registered with full permissions and allowed to query across all SharePoint Online content to include user’s private OneDrive for Business content. When this change is implemented, queries using the Site.Read.All permissions level or greater will be throttled at 25 QPS.

The search query will return with a 429 response and you can simply retry the query. When waiting for 429 recovery, you should ensure to pause all search query requests you may be making to the service using similar app-only permission. Making additional calls while receiving throttle responses will extend the time it takes for your app to become unthrottled.

As we scale our system, we realize the importance of hardening the system to run it efficiently and also to protect the system and hence this change. This change is expected to rollout beginning August 2020 into the Fall of 2020.
More info: https://docs.microsoft.com/en-us/sharepoint/dev/general-development/how-to-avoid-getting-throttled-or-blocked-in-sharepoint-online

Status	In Development
Product	SharePoint
Release phase	General Availability
Release date	October CY2021
Platform	Web
Cloud Instance	Worldwide (Standard Multi-Tenant)
Created	2020-06-11
Updated	2021-10-02
Roadmap ID	64963
Roadmap Link	https://www.microsoft.com/microsoft-365/roadmap?featureid=64963