Hi Sandeep,
API Gateway has two policies - Under Threat protection, we have a Denial of service through which you can throttle the incoming requests. Please note that this global setting applies to all the API calls coming to the system.
We also have a Traffic optimization policy which can rate limit the API calls for the duration configured. We can implement both of the policies at the same time.
Note: Denial of Service policy is global, whereas Traffic optimization can be configured globally for multiple APIs and at the API level.
If you use the on-premise variant, we can configure the thread pool size in the Integration server Admin page.
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