The doc mentions match_path in one place but the correct syntax is path_match which is mentioned everywhere else. Using the wrong string leads to errors because the mapping becomes too greedy, and matches things it shouldn't.
This is to prevent mapping explosion when dynamic keys such as UUID are used as field names. index.mapping.total_fields.limit specifies the total number of fields an index can have. An exception will be thrown when the limit is reached. The default limit is 1000. Value 0 means no limit. This setting is runtime adjustable
Closes#11443