# One GC problem

**URL:** <https://discuss.elastic.co/t/one-gc-problem/53761>\
**Category:** Elasticsearch\
**Created:** [June 23, 2016, 9:47am UTC](https://discuss.elastic.co/t/one-gc-problem/53761 "2016-06-23T09:47:40Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![makeyang](https://avatars.discourse-cdn.com/v4/letter/m/f05b48/32.png) [@makeyang](https://discuss.elastic.co/u/makeyang)\
**Post date:** [June 23, 2016, 9:47am UTC](https://discuss.elastic.co/t/one-gc-problem/53761/1 "2016-06-23T09:47:40Z")

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one of my gateway node is assiged 1 GB heap memory and the traffic is very little. but it happens long GC time by time. can anybody give any hints about it?  
ES log:

```auto
[2016-06-23 03:53:01,518][WARN][monitor.jvm] [gw_172.20.122.111:9202] [gc][young][1232891][28] duration [1s], collections [1]/[1.2s], total [1s]/[22.2s], memory [298.7mb]->[27.3mb]/[989.8mb], all_pools {[young] [273mb]->[1.9mb]/[273mb]}{[survivor] [1.1mb]->[764.3kb]/[34.1mb]}{[old] [24.6mb]->[24.6mb]/[682.6mb]}
[2016-06-23 16:56:01,792][WARN][monitor.jvm] [gw_172.20.122.111:9202] [gc][young][1279864][29] duration [1.3s], collections [1]/[2.3s], total [1.3s]/[23.6s], memory [298.3mb]->[27.4mb]/[989.8mb], all_pools {[young] [272.9mb]->[2.1mb]/[273mb]}{[survivor] [764.3kb]->[697.2kb]/[34.1mb]}{[old] [24.6mb]->[24.6mb]/[682.6mb]}

```

os:  
CentOS release 6.6 (Final)  
2.6.32

JDK:  
jdk1.8.0\_60

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<div class="post-metadata">

**Author:** ![nik9000](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/nik9000/32/44947_2.png) [@nik9000](https://discuss.elastic.co/u/nik9000)\
**Post date:** [June 23, 2016, 12:56pm UTC](https://discuss.elastic.co/t/one-gc-problem/53761/2 "2016-06-23T12:56:58Z")

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It is freeing pretty much all of the memory. With a 1GB I expect a young GC to be way faster than that. I wonder if you are swapping?

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<div class="post-metadata">

**Author:** ![makeyang](https://avatars.discourse-cdn.com/v4/letter/m/f05b48/32.png) [@makeyang](https://discuss.elastic.co/u/makeyang)\
**Post date:** [June 24, 2016, 1:44am UTC](https://discuss.elastic.co/t/one-gc-problem/53761/3 "2016-06-24T01:44:07Z")

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how do I tell whether a running node swapping or not?

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<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, 10:40pm UTC](https://discuss.elastic.co/t/one-gc-problem/53761/4 "2017-07-05T22:40:54Z")

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