In 5.0, the search slow log switched to the multi-line format with no option to get back to the origin single-line format that was used prior to 5.0 by default. This commit removes the reformat option from the search slow log and returns the search slow log back to the single-line format.
Closes#21711
This commit fixes two issues with the slow log docs:
- clarifies that these settings are per index
- updates index slow log configuration for Log4j 2
Relates #20976
Instead of logging the entire `_source` in the indexing slowlog we log by
default just the first 1000 characters - this is controlled by the
`index.indexing.slowlog.source` settings and can be set to `true` to log the
whole `_source`, `false` to log none of it, and a number to log at most that
many characters.
Closes#4485
Igor Motov
Jason Tedor
Sakthipriyan Vairamani
Nik Everett
Clinton Gormley
Kouhei Sutou
Lee Hinman