title: ElasticSearch Performance Optimization in Multi-Index Search over a Small Data Set per Index
body: <p>We have different document structures/schema that we on-board into different elasticsearch indices. We have ~50 such indices, and one of our primary use cases is to perform search across all these document types i.e. across all 50 indices. Data size within each index is ~10-20 GB, thus each index easily fits into a single shard.
  I am looking for ways to optimize the performance in search across these 50 indices. We have a particular common field across all these indices which is available within a user's search request, and could be used for sharding within each index if we had more than one shards per index. Not sure if we could make use of it somehow to optimize the performance for this multi-index search, or any other alternate options.</p>