The changes related to search are as follows:
- By default, the adaptive replica selection, cluster.routing.use_adaptive_replica_selection, is enabled to send copies of data to replicas. You may disable it to use the old round-robin method as in 6.x.
- In the following error situations, a bad request (400) will be returned instead of an internal server error (500):
- The resulting window is too large, from + size must be less than or equal to: [x] but was [y].
- Cannot use the [sort] option in conjunction with [rescore].
- The rescore window, [x], is too large.
- The number of slices, [x], is too large.
- Keep alive for scroll, [x], is too large.
- In adjacency matrix aggregation, the number of filters exceeds the max limit.
- An org.elasticsearch.script.ScriptException ...