Hi @Maceo Wu ,
Microsoft Graph is cloud born APIs that have the latest improvements and optimizations. In general, Microsoft Graph consumes less resource than CSOM and REST to achieve the same functionality. Hence, adopting Microsoft Graph can improve application's performance and reduce throttling.
If you do run into throttling, we require leveraging the Retry-After HTTP header to ensure minimum delay until the throttle is removed.
The Retry-After HTTP header is the fastest way to handle being throttled because SharePoint Online dynamically determines the right time to try again. In other words, aggressive retries work against you because even though the calls fail, they still accrue against your usage limits. Following the Retry-After HTTP header will ensure the shortest delay.
For information about ways to monitor your SharePoint Online activity, see Diagnosing performance issues with SharePoint Online.
For a broader discussion of throttling on the Microsoft Cloud, see Throttling Pattern.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.