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1-10-07. The Root Object

The uppermost level of a mapping is known as the root object. It may contain the following:mapping의 최상위 단계는 root object 로 알려져 있다. 아래와 같은 것을 포함하고 있다.A properties section, which lists the mapping for each field that a document may containdocument가 가지게 될, 각 field의 mapping을 나열하는 properties 부분.Various metadata fields, all of which start with an underscore, such as _type, _id, and _source_type, _id, _..

1-11-2. Dynamically Updatable

The next problem that needed to be solved was how to make an inverted index updatable without losing the benefits of immutability? The answer turned out to be: use more than one index.해결해야 할 다음 문제는, 불변성의 장점을 잃지 않고, inverted index를 업데이트 가능하도록 만드는 방법이다. 답은 하나 이상의 index를 사용하는 것이다.Instead of rewriting the whole inverted index, add new supplementary indices to reflect more-recent changes. Each invert..

4-10-4. Limiting Memory Usage

Once analyzed strings have been loaded into fielddata, they will sit there until evicted (or your node crashes). For that reason it is important to keep an eye on this memory usage, understand how and when it loads, and how you can limit the impact on your cluster.일단 analyzed string이 fielddata에 로드되면, 그것들은 추출될 (또는 node가 crash)) 때까지 그 곳에 있을 것이다. 이런 이유로 이런 메모리 사용을 관찰하고, 그것이 언제 어떻게 로드되는지를 이해하고, clus..

2.X/4. Aggregations 2017.09.23

6-4-01. The Unit of Scale

In Dynamically Updatable Indices, we explained that a shard is a Lucene index and that an Elasticsearch index is a collection of shards. Your application talks to an index, and Elasticsearch routes your requests to the appropriate shards.Dynamically Updatable Indices에서, shard는 Lucene의 index 이고, Elasticsearch의 index는 shard의 집합이라고 설명했었다. 응용프로그램이 index에 request하면, Elasticsearch는 적절한 shard에 해당 reque..

7-1-5. Index Stats

So far, we have been looking at node-centric statistics: How much memory does this node have? How much CPU is being used? How many searches is this node servicing?지금까지, node 중심 의 통계를 살펴봤다. 이 node가 가지고 있는 메모리가 얼마인지? CPU가 얼마나 사용되고 있는지? 이 node가 서비스하고 있는 검색은 얼마나 많은지?Sometimes it is useful to look at statistics from an index-centric perspective: How many search requests is this index receiving? How m..