# Deep aggregations **URL:** \ **Category:** Elasticsearch\ **Created:** [August 16, 2016, 10:40pm UTC](https://discuss.elastic.co/t/deep-aggregations/58197 "2016-08-16T22:40:19Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Karthik\_Ramachandran](https://avatars.discourse-cdn.com/v4/letter/k/f19dbf/32.png) [@Karthik\_Ramachandran](https://discuss.elastic.co/u/Karthik_Ramachandran)\ **Post date:** [August 16, 2016, 10:40pm UTC](https://discuss.elastic.co/t/deep-aggregations/58197/1 "2016-08-16T22:40:19Z")
All, I need to aggregations at deep level viz. Nesting more than 6 terms (non\_analyzed) with some search on analyzed content. Trying to answer the below query as recommendation is that avoid deep aggregation. I saw a comment that and issue around deep aggregation is fixed in 1.2. We are using 2.x version now. Queries 1. How deep I can go viz. Levels? I don't think there is a restriction, but not sure! 2. Best practices around deep aggregations with NESTED content type:nested in mapping. Below are some we are following already. --- Aggregate at parent level, followed by nested --- Avoid reverse\_nesting unless it is absolutely needed --- Avoid nesting when we could aggregate without nesting viz. Aggregate on only one nested element and rest are parent. In this case include\_in\_parent on nested helps not to nest during queries as relation within nested object attribute are not needed to look at --- Breadth\_first on high-cardinality columns with additional filter Data size : 20 TB (representing 1 yr) and increasing on rolling 1 year Node 30 Data nodes and 4 client nodes Some observations - High JVM usage and CPU usage on Aggregations. The above usage is required due to the fact that Pivot Table is a major request from business on search+aggregations. We are also looking at alternatives like Spark etc. to see if we can get aggregations. 90% of aggregations queries hit all nodes (for a replica set) as the quey spans across year. Thanks for inputs ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 5, 2017, 10:27pm UTC](https://discuss.elastic.co/t/deep-aggregations/58197/2 "2017-07-05T22:27:27Z")