【Elasticsearch】elasticsearch 分片

1 Overview

1.1 What is a Shard?

It is introduced in the document below
https://www.elastic.co/guide/cn/elasticsearch/guide/current/kagillion-shards.html

1. The bottom layer of a fragment is a Lucene index, which consumes a certain amount of file handles, memory, and CPU operation.

2. Every search request needs to hit every shard in the index. It is good if every shard is on a different node, but it 同一个节点上竞争is a bit bad if multiple shards need to use the same resource.

3. 计算相关度The term statistics used is yes 基于分片. If there are many shards, each with very little data will lead to very low correlation.

The relationship between clusters, nodes, and shards is introduced in the official document

https://www.elastic.co/