ConfigClient Unnecessarily Triggers Full Registry Fetches on Every Heartbeat

[tdkgo]

Problem:
ConfigClient's ConfigServerInstanceMonitor listens to all HeartbeatEvents and unconditionally refreshes ConfigServer addresses, often triggering full Eureka registry fetches even when ConfigServer instances haven't changed.

ConfigClient refreshes addresses on every heartbeat, regardless of actual ConfigServer changes

Address refresh may trigger full registry fetch from Eureka

Impact:

Unnecessary load on Eureka Server

Excessive network traffic in large deployments

Reduced system scalability

Proposed Solution:
Introduce smart refresh strategy that only updates ConfigServer addresses when they actually change, not on every heartbeat.

[ryanjbaxter]

So you are saying this check is not working?
https://github.com/spring-cloud/spring-cloud-config/blob/main/spring-cloud-config-client/src/main/java/org/springframework/cloud/config/client/ConfigServerInstanceMonitor.java#L80

[tdkgo]

Every time a HeartbeatEvent is monitored, refresh() will be called.

Current version:
<spring.version>6.2.15</spring.version>
<spring-boot.version>3.5.9</spring-boot.version>
<spring-cloud.version>2025.0.1</spring-cloud.version>

[ryanjbaxter]

Even if the refresh method is called on every HeartbeatEvent I am still not convinced that this causes a request to the Eureka server to fetch the service instances.

The refresh method will eventually call ConfigServerInstanceProvider which will use EurekaDiscoveryClient which uses CloudEurekaClient which maintains a cache of the service instances.

[spring-cloud-issues]

If you would like us to look at this issue, please provide the requested information. If the information is not provided within the next 7 days this issue will be closed.

[spring-cloud-issues]

Closing due to lack of requested feedback. If you would like us to look at this issue, please provide the requested information and we will re-open the issue.