关于 ES 的文件格式（qbit）

前言

• 本文对 Elasticsearch 7.10 适用
• Elasticsearch 7.10 对应 Lucene 8.7
• Lucene 8.7 关于扩展名的官方文档 https://lucene.apache.org/cor...

• 相关阅读： elasticsearch 百亿级数据检索案例与原理

逐个解释

segments_N

• Name: Segments File
• Brief Description: Stores information about a commit point

write.lock

• Name: Lock File
• Brief Description: The Write lock prevents multiple IndexWriters from writing to the same file.

.si

• Name: Segment Info
• Brief Description: Stores metadata about a segment

.cfs, .cfe

• Name: Compound File
• Brief Description: An optional "virtual" file consisting of all the other index files for systems that frequently run out of file handles.

.fnm

• Name: Fields
• Brief Description: Stores information about the fields
• field 数据元信息

.fdx

• Name: Field Index
• Brief Description: Contains pointers to field data

.fdt

• Name: Field Data
• Brief Description: The stored fields for documents

.tim

• Name: Term Dictionary
• Brief Description: The term dictionary, stores term info
• 倒排表指针

.tip

• Name: Term Index
• Brief Description: The index into the Term Dictionary
• 词典索引

.doc

• Name: Frequencies
• Brief Description: Contains the list of docs which contain each term along with frequency
• 包含 term 和频率的文档列表

.pos

• Name: Positions
• Brief Description: Stores position information about where a term occurs in the index

.pay

• Name: Payloads
• Brief Description: Stores additional per-position metadata information such as character offsets and user payloads

.nvd, .nvm

• Name: Norms
• Brief Description: Encodes length and boost factors for docs and fields
• .nvd: Norms data
• .nvm: Norms metadata

.dvd, .dvm

• Name: Per-Document Values
• Brief Description: Encodes additional scoring factors or other per-document information.
• .dvd: DocValues data，DocValues 数据
• .dvm: DocValues metadata，DocValues 元数据

.tvx

• Name: Term Vector Index
• Brief Description: Stores offset into the document data file

.tvd

• Name: Term Vector Data
• Brief Description: Contains term vector data.

.liv

• Name: Live Documents
• Brief Description: Info about what documents are live

.dii, .dim

• Name: Point values
• Brief Description: Holds indexed points, if any

本文出自 qbit snap