Backport of #58898.
Part of #48366. Now that there is a dedicated API for dangling indices, the auto-import
behaviour can default to off. Also add a note to the breaking changes for 7.9.0.
This commit increases the default write queue size to 10000. This is to
allow a greater number of pending indexing requests. This work is safe
as we have added additional memory limits. Relates to #59263.
Restoring from a snapshot (which is a particular form of recovery) does not currently take recovery throttling into account
(i.e. the `indices.recovery.max_bytes_per_sec` setting). While restores are subject to their own throttling (repository
setting `max_restore_bytes_per_sec`), this repository setting does not allow for values to be configured differently on a
per-node basis. As restores are very similar in nature to peer recoveries (streaming bytes to the node), it makes sense to
configure throttling in a single place.
The `max_restore_bytes_per_sec` setting is also changed to default to unlimited now, whereas previously it was set to
`40mb`, which is the current default of `indices.recovery.max_bytes_per_sec`). This means that no behavioral change
will be observed by clusters where the recovery and restore settings were not adapted.
Relates https://github.com/elastic/elasticsearch/issues/57023
Co-authored-by: James Rodewig <james.rodewig@elastic.co>
Rory Hunter
Tim Brooks
Yannick Welsch
markharwood
Lisa Cawley
Stuart Tettemer