statistics on different operations happening on an index
The number of docs / deleted docs (docs not yet merged out).
Note, affected by refreshing the index.
The size of the index.
Indexing statistics, can be combined with a comma separated list of types to provide document type level stats.
Get statistics, including missing stats.
Search statistics including suggest statistics.
You can include statistics for custom groups by adding an extra groups parameter
(search operations can be associated with one or more groups).
The groups parameter accepts a comma separated list of group names.
Use _all to return statistics for all groups.
Retrieve the memory use of the open segments.
Optionally, setting the include_segment_file_sizes flag,
report the aggregated disk usage of each one of the Lucene index files.
Completion suggest statistics.
Shard request cache statistics.
# Get back stats for merge and refresh only for all indices
# Get back stats for type1 and type2 documents for the my_index index
# Get back just search stats for group1 and group2
primaries are the values for only the primary shards
total are the cumulated values for both primary and replica shards.
In order to get back shard level stats, set the level parameter to shards.
Note, as shards move around the cluster,
their stats will be cleared as they are created on other nodes.
On the other hand, even though a shard "left" a node,
that node will still retain the stats that shard contributed to.
segments information 段信息
The key of the JSON document is the name of the segment.
This name is used to generate file names:
all files starting with this segment name in the directory of the shard belong to this segment.
A generation number that is basically incremented when needing to write a new segment.
The segment name is derived from this generation number.
The number of non-deleted documents that are stored in this segment.
The number of deleted documents that are stored in this segment.
It is perfectly fine if this number is greater than 0,
space is going to be reclaimed when this segment gets merged.
The amount of disk space that this segment uses, in bytes.
Segments need to store some data into memory in order to be searchable efficiently.
This number returns the number of bytes that are used for that purpose.
A value of -1 indicates that Elasticsearch was not able to compute this number.
Whether the segment has been sync’ed on disk.
Segments that are committed would survive a hard reboot.
No need to worry in case of false,
the data from uncommitted segments is also stored in the transaction log
so that Elasticsearch is able to replay changes on the next start.
如果没有写入磁盘，重启时会使用 transaction log 重放变更操作
Whether the segment is searchable.
A value of false would most likely mean that the segment has been written to disk
but no refresh occurred since then to make it searchable.
The version of Lucene that has been used to write this segment.
Whether the segment is stored in a compound file.
When true, this means that Lucene merged all files
from the segment in a single one in order to save file descriptors.
段是否存储在复合文件中。 如果为true 说明段文件合并过了，
the timings in milliseconds of the various stages of recovery: index retrieval, translog replay, and index start time.
active_only=true will cause only on-going recoveries to be reported.
Display a detailed view. This is primarily useful for viewing the recovery of physical index files. Default: false.
Display only those recoveries that are currently on-going. Default: false.
init: Recovery has not started
index: Reading index meta-data and copying bytes from source to destination
start: Starting the engine; opening the index for use
translog: Replaying transaction log
True if shard is primary, false otherwise
Timestamp of recovery start
Timestamp of recovery finish
Total time to recover shard in milliseconds
repository description if recovery is from a snapshot
description of source node otherwise
Statistics about physical index recovery
Statistics about translog recovery
Statistics about time to open and start the index
Indices Shard Stores
Provides store information for shard copies of indices.
at least one unassigned replica
green yellow red
"allocation" : "primary" | "replica" | "unused"
Any exception encountered while opening the shard index or from earlier engine failure
elasticsearch aerospike kafka副本数设置