# How do we know how much memory we need? **URL:** \ **Category:** Elasticsearch\ **Created:** [August 26, 2015, 2:35pm UTC](https://discuss.elastic.co/t/how-do-we-know-how-much-memory-we-need/28116 "2015-08-26T14:35:48Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![javadevmtl](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/javadevmtl/32/45613_2.png) [@javadevmtl](https://discuss.elastic.co/u/javadevmtl)\ **Post date:** [August 26, 2015, 2:35pm UTC](https://discuss.elastic.co/t/how-do-we-know-how-much-memory-we-need/28116/1 "2015-08-26T14:35:48Z")
Using 1.6.0 We use daily index pattern so far 11 indexes/days We have about 34 million docs per day, relatively small about 3K bytes each doc. Indexes have 4 shards + 1 replica. Each index is about 8GB size on disk (includes replica) Each shards reports about 6mb memory usage in the segments section. So is the following right? 11 indexes x 8 shards(per index) x 6mb = 528mb / 4 nodes = 132mb per node + what ever filter cache, field data etc... So for 365 days we would need, about 5GB per node + what ever for operational. Then depending on usage we can close older indexes to free memory. And maybe add a couple more boxes and move some indexes there type of thing... ---
**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, 11:53pm UTC](https://discuss.elastic.co/t/how-do-we-know-how-much-memory-we-need/28116/2 "2017-07-05T23:53:43Z")