edit-icon download-icon

Rate limiting and degradation overview

Last Updated: Jan 29, 2018

The rate liming and service degradation feature of EDAS solves slow system responses or crashes caused by high pressure of the backend core services. This feature is generally used in high-traffic scenarios, for example, flash sale, shopping spree, great promotion, and anti-click farming scams.

Rate limiting and degradation

This feature is used to control the traffic threshold or adjust the ratio. When a frontend website encounters high traffic access, the traffic is controlled to prevent damage to the backend core systems and service unavailability. By adjusting the traffic threshold, the maximum traffic volume of the system is controlled to ensure secure and stable operation of the systems.

Basic principle

After a rate limiting and throttling module code is configured for a service provider and a rate limiting policy is configured on EDAS, the service provider is enabled with the rate limiting and throttling function. When a service consumer calls the service provider, all access requests are calculated by the rate limiting module. If the number of calls of the service consumer exceeds the preset threshold in a specific period, the throttling policy is triggered.

Rate limiting rule

Service degradation

Service degradation is to lower the priority of timed-out service calls from non-core service providers to ensure the availability of core service consumers.

Basic principle

After a degradation module code is configured for a service consumer and a degradation policy is configured on EDAS, the service consumer is enabled with the degradation function. When the service consumer calls a service provider, if the response time of the service provider exceeds the preset threshold, the degradation policy is triggered.

Degrade rule

Thank you! We've received your feedback.