When using the default cache, the following warning is logged:
Spring Cloud LoadBalancer is currently working with the default cache. You can switch to using Caffeine cache, by adding it to the classpath.
As clarified in the docs via #991, this is unnecessary if using a Service Discovery implementation which itself performs caching, such as EurekaDiscoveryClient.
IMO this is something that the framework can/should take into account. Supressing the warning if a known DiscoveryClient implementation is on the classpath (e.g. via @ConditionalOnClass or even a simple Class lookup).
A user seeing this warning will add e.g. Caffeine as a cache mechanism while potentially then introducing a buggy double-caching layer, unless they carefully read a specific section of the docs and/or are using a caching mechanism that does not contain caching itself (e.g. EurekaDiscoveryClient).