# Elasticsearch io wait **URL:** \ **Category:** Elasticsearch\ **Created:** [October 14, 2016, 9:03pm UTC](https://discuss.elastic.co/t/elasticsearch-io-wait/63085 "2016-10-14T21:03:58Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![sharon.c](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/sharon.c/32/16076_2.png) [@sharon.c](https://discuss.elastic.co/u/sharon.c)\ **Post date:** [October 14, 2016, 9:03pm UTC](https://discuss.elastic.co/t/elasticsearch-io-wait/63085/1 "2016-10-14T21:03:58Z")
I have a 4 nodes elasticsearch cluster (64G RAM, 8 CPUs), data stream in at the speed of 800-3000 messages per second, mainly usage is for aggregation. It was working very well for a few month without problem, but today, it has cpu usage 100% when io wait was high, and messages are lost. I suspect it is because of searching query is too demanding, is there any way I can check slow query logs? Newrelic screen catch ![](https://us1.discourse-cdn.com/elastic/original/2X/4/4ffe75fc1af504790efd1daeaae437599affe388.png) Marvel screen catch: ![](https://us1.discourse-cdn.com/elastic/original/2X/c/c5d8223467244d7bdbdf64ef68623fdbb67de955.png) ![](https://us1.discourse-cdn.com/elastic/original/2X/3/33413509214a1c9fe24595e960c6365eaa879a3c.png) Zoomed in marvel screen catch at the peak time: ![](https://us1.discourse-cdn.com/elastic/original/2X/7/762462ed19d4790c53fbbab4e06973dfd8e7c8e5.png) ---
**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, 10:12pm UTC](https://discuss.elastic.co/t/elasticsearch-io-wait/63085/2 "2017-07-05T22:12:08Z")