How can search results be cached? [closed]

Question

How do I implement caching mechanism of search results as on stackoverflow? How does elastic search and lucene deal with caching?

Answer 1

As of now, you can cache in two different ways within Elasticsearch

1. Filter cache - Here if you can offload as many constraints which don't take part in scoring of results, you can have segment level caches for that particular filter alone. This along with warmer API provides some decent amount in memory based caching for the filters applied alone
2. Shard request cache * - You can cache the results ( Other than hits) on query level. This is pretty new feature and should provide a good amount of caching. But still _source needs to be still taken the shards.

Within Elasticsearch you can exploit these features to attain a good amount of caching. Also, you can explore other caching option external to Elasticsearch to memcache or other in memory caches.

• previously called shared query cache