Today we require users to prepare their indices for split operations.
Yet, we can do this automatically when an index is created which would
make the split feature a much more appealing option since it doesn't have
any 3rd party prerequisites anymore.
This change automatically sets the number of routinng shards such that
an index is guaranteed to be able to split once into twice as many shards.
The number of routing shards is scaled towards the default shard limit per index
such that indices with a smaller amount of shards can be split more often than
larger ones. For instance an index with 1 or 2 shards can be split 10x
(until it approaches 1024 shards) while an index created with 128 shards can only
be split 3x by a factor of 2. Please note this is just a default value and users
can still prepare their indices with `index.number_of_routing_shards` for custom
splitting.
NOTE: this change has an impact on the document distribution since we are changing
the hash space. Documents are still uniformly distributed across all shards but since
we are artificually changing the number of buckets in the consistent hashign space
document might be hashed into different shards compared to previous versions.
This is a 7.0 only change.
* Remove the setting from the yml tests and replace with tests using
`join` field. We can't use the setting in yml tests without lots of
backflips but we have `ReindexParentChildTests` for the coverage.
There weren't tests for `join` field with reindex before this. Adding
these tests discovered #25363.
* Remove the setting from `ReindexParentChildTests` and replace with
`index.version.created=V_5_6_0`. This test can be entirely removed
when legacy parent/child support is dropped from core.
* Port the yml tests that set _parent into integ tests so they
can set the index created version. These tests can be removed
when we drop support for _parent in core.
* Port a delete-by-query test for filtering based on type to an
`ESIntegTestCase` so it can use `index.version.created=5.6.0` to
setup documents of multiple types. This whole feature can be dropped
when we no longer support multiple types per index.
Relates to #24961
This commit adds back "id" as the key within a script to specify a
stored script (which with file scripts now gone is no longer ambiguous).
It also adds "source" as a replacement for "code". This is in an attempt
to normalize how scripts are specified across both put stored scripts and script usages, including search template requests. This also deprecates the old inline/stored keys.
This commit renames all rest test files to use the .yml extension
instead of .yaml. This way the extension used within all of
elasticsearch for yaml is consistent.
* Add parent-join module
This change adds a new module named `parent-join`.
The goal of this module is to provide a replacement for the `_parent` field but as a first step this change only moves the `has_child`, `has_parent` queries and the `children` aggregation to this module.
These queries and aggregations are no longer in core but they are deployed by default as a module.
Relates #20257
Simon Willnauer
Anton Pozhidaev
Michael Basnight
Martijn van Groningen
Nik Everett
Ryan Ernst
Jim Ferenczi