# How does an index's document count affect performance? **URL:** \ **Category:** Elasticsearch\ **Created:** [February 29, 2016, 11:33pm UTC](https://discuss.elastic.co/t/how-does-an-indexs-document-count-affect-performance/43059 "2016-02-29T23:33:14Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![bguyzer](https://avatars.discourse-cdn.com/v4/letter/b/50afbb/32.png) [@bguyzer](https://discuss.elastic.co/u/bguyzer)\ **Post date:** [February 29, 2016, 11:33pm UTC](https://discuss.elastic.co/t/how-does-an-indexs-document-count-affect-performance/43059/1 "2016-02-29T23:33:14Z")
Are there any metrics, posts, or otherwise good information regarding how document size as well as the total document count on an index affects search performance? I understand other mitigating factors such as mapping, analyzer, etc., but how do the sheer numbers line up? For example, I have a basic mapping with 5 general fields, no nesting, or anything special. How can I estimate search performance would be affected from say, 100k documents to 100 million or 1 Billion documents? ---
**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\ **Post date:** [February 29, 2016, 11:44pm UTC](https://discuss.elastic.co/t/how-does-an-indexs-document-count-affect-performance/43059/2 "2016-02-29T23:44:29Z")
It can depend on a number of factors, so the best way to know is to benchmark using realistic data and queries on your hardware. ---
**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, 11:12pm UTC](https://discuss.elastic.co/t/how-does-an-indexs-document-count-affect-performance/43059/3 "2017-07-05T23:12:44Z")