Package io.javaoperatorsdk.operator.processing.event.source.cache

Class CaffeineBoundedItemStores

java.lang.Object
io.javaoperatorsdk.operator.processing.event.source.cache.CaffeineBoundedItemStores
public class CaffeineBoundedItemStores extends Object
A factory for Caffeine-backed BoundedItemStore. The implementation uses a CaffeineBoundedCache to store resources and progressively evict them if they haven't been used in a while. The idea about CaffeinBoundedItemStore-s is that, caffeine will cache the resources which were recently used, and will evict resource, which are not used for a while. This is ideal for startup performance and efficiency when all resources should be cached to avoid undue load on the API server. This is why setting a maximal cache size is not practical and the approach of evicting least recently used resources was chosen. However, depending on controller implementations and domains, it could happen that some / many of these resources are then seldom or even reconciled anymore. In that situation, large amounts of memory might be consumed to cache resources that are never used again.

Note that if a resource is reconciled and is not present anymore in cache, it will transparently be fetched again from the API server. Similarly, since associated secondary resources are usually reconciled too, they might need to be fetched and populated to the cache, and will remain there for some time, for subsequent reconciliations.

  • Method Details

    • boundedItemStore

      public static <R extends io.fabric8.kubernetes.api.model.HasMetadata> BoundedItemStore<R> boundedItemStore(io.fabric8.kubernetes.client.KubernetesClient client, Class<R> rClass, Duration accessExpireDuration)
      Type Parameters:
      R - resource type
      Parameters:
      client - Kubernetes Client
      rClass - resource class
      accessExpireDuration - the duration after resources is evicted from cache if not accessed.
      Returns:
      the ItemStore implementation

    • boundedItemStore

      public static <R extends io.fabric8.kubernetes.api.model.HasMetadata> BoundedItemStore<R> boundedItemStore(io.fabric8.kubernetes.client.KubernetesClient client, Class<R> rClass, com.github.benmanes.caffeine.cache.Cache<String,R> cache)