Invalidating query cache entries key
Caches are tremendously useful in a wide variety of use cases.
For example, you should consider using caches when a value is expensive to compute or retrieve, and you will need its value on a certain input more than once. No observable state associated with this cache is modified until loading completes.
We use the Spring declarative caching by means of the @Cacheable annotation: So our application is running.
The query cache is a very good fit for the logging use case, where only the most recent index is being actively updated — results from older indices will be served directly from the cache. Cached results are invalidated automatically whenever the shard refreshes, but only if the data in the shard has actually changed.
If the cache is full, the least recently used cache keys will be evicted.
The cache can be expired manually with the setting to specify a TTL for cached results, but there should be no reason to do so.
You must decide: when is it not worth keeping a cache entry?
Guava provides three basic types of eviction: size-based eviction, time-based eviction, and reference-based eviction.