# Too many threads on elasticsearch

**URL:** <https://discuss.elastic.co/t/too-many-threads-on-elasticsearch/52095>\
**Category:** Elasticsearch\
**Created:** [June 7, 2016, 2:52pm UTC](https://discuss.elastic.co/t/too-many-threads-on-elasticsearch/52095 "2016-06-07T14:52:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![MaKro](https://avatars.discourse-cdn.com/v4/letter/m/bbe5ce/32.png) [@MaKro](https://discuss.elastic.co/u/MaKro)\
**Post date:** [June 7, 2016, 2:52pm UTC](https://discuss.elastic.co/t/too-many-threads-on-elasticsearch/52095/1 "2016-06-07T14:52:15Z")

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Hi.

I've got Elasticsearch cluster with three nodes.  
I'm getting stacktraces like this:  
java.lang.Thread.State: RUNNABLE  
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)  
at sun.nio.ch.EPollArrayWrapper.poll(EPollArrayWrapper.java:269)  
at sun.nio.ch.EPollSelectorImpl.doSelect(EPollSelectorImpl.java:79)  
at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:87)  
locked \<0x0000000406628550\> (a sun.nio.ch.Util$2)  
locked \<0x0000000406628540\> (a java.util.Collections$UnmodifiableSet)  
locked \<0x0000000406628428\> (a sun.nio.ch.EPollSelectorImpl)  
at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:98)  
at org.elasticsearch.common.netty.channel.socket.nio.SelectorUtil.select(SelectorUtil.java:68)  
at org.elasticsearch.common.netty.channel.socket.nio.AbstractNioSelector.select(AbstractNioSelector.java:434)  
at org.elasticsearch.common.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:212)  
at org.elasticsearch.common.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:89)  
at org.elasticsearch.common.netty.channel.socket.nio.NioWorker.run(NioWorker.java:178)  
at org.elasticsearch.common.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108)  
at org.elasticsearch.common.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)  
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)  
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)  
at java.lang.Thread.run(Thread.java:745)

From what I have read, it looks like a netty bug, but it should be fixed in java 1.7.0\_11 and higher. I'm using java 1.7.0\_67.  
Elasticsearch version is 1.7.3  
Those are nodes stats which I assume are related:

```
  "http" : {
    "current_open" : 6,
    "total_opened" : 405481
  }

```

Results are very similar on each node. There should be only one instance of java client which connects to ElasticSearch.

Any ideas what may cause such errors? is it a problem with java client, configuration or maybe it's a bug?

---

<div class="post-metadata">

**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, 10:45pm UTC](https://discuss.elastic.co/t/too-many-threads-on-elasticsearch/52095/2 "2017-07-05T22:45:35Z")

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