ReduceSearchPhaseException[Failed to execute phase [fetch], [reduce] ; shardFailures {[4B1_GB-bROOd48bW0k9KUw][file_v6][3]: EsRejectedExecutionException[rejected execution (queue capacity 4000) on org.elasticsearch.search.action.SearchServiceTransportAction$23@5adc5d9e]}]; nested: EsRejectedExecutionException[rejected execution (queue capacity 4000) on org.elasticsearch.action.search.type.TransportSearchQueryThenFetchAction$AsyncAction$2@3af2573a];