Chapter 6. Low-level Index Control
In the previous chapter, we talked about general shards and the index architecture. We started by learning how to choose the right amount of shards and replicas, and we used routing during indexing and querying, and in conjunction with aliases. We also discussed shard allocation behavior adjustments, and finally, we looked at what query execution preference can bring us.
In this chapter, we will take a deeper dive into more low-level aspects of handling shards in Elasticsearch. By the end of this chapter, you will have learned:
- Altering the Apache Lucene scoring by using different similarity models
- Altering index writing by using codes
- Near real-time indexing and querying
- Data flushing, index refresh, and transaction log handling
- I/O throttling
- Segment merge control and visualization
- Elasticsearch caching
