Elasticsearch 2.4.1 Cluster stuck on Heap high usage

If you are using groovy scripts look at this topics: https://discuss.elastic.co/t/elastic-search-using-a-lot-of-memory-gc-thrashing/48695 and https://discuss.elastic.co/t/heap-issue-after-upgrading-elasticsearch-from-v1-7-5-to-v2-4-1/65612