# Elasticsearch Disk Usage Internals **URL:** \ **Category:** Elasticsearch\ **Created:** [December 15, 2019, 8:48pm UTC](https://discuss.elastic.co/t/elasticsearch-disk-usage-internals/211924 "2019-12-15T20:48:10Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![jaredvacanti](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jaredvacanti/32/56645_2.png) [@jaredvacanti](https://discuss.elastic.co/u/jaredvacanti)\ **Post date:** [December 15, 2019, 8:48pm UTC](https://discuss.elastic.co/t/elasticsearch-disk-usage-internals/211924/1 "2019-12-15T20:48:10Z")
I'm trying to get a better understanding of elasticsearch internals - I've noticed when monitoring the disk usage of my elasticsearch cluster that there are periodic spikes in both master and data nodes during typical operation. This cluster has metric indices (streaming data) and other standard indices. Is this some sort of vacuuming process, or something else? I've attached a screenshot to show the spikes. ![Screenshot from 2019-12-15 14-37-54](https://us1.discourse-cdn.com/elastic/original/3X/e/0/e0ab0e4402d3999f674ddd5750a33a9c520fd478.png) ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [December 16, 2019, 12:23am UTC](https://discuss.elastic.co/t/elasticsearch-disk-usage-internals/211924/2 "2019-12-16T00:23:59Z")
That could be explained when segment merge operations are happening on very big segments. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [January 13, 2020, 12:24am UTC](https://discuss.elastic.co/t/elasticsearch-disk-usage-internals/211924/3 "2020-01-13T00:24:05Z")
Closed on January 13, 2020, 12:24am UTC This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.