# Elastic indexing rate decreased after a while

**URL:** https://discuss.elastic.co/t/elastic-indexing-rate-decreased-after-a-while/34584
**Category:** Elasticsearch
**Created:** [November 14, 2015, 7:20am UTC](https://discuss.elastic.co/t/elastic-indexing-rate-decreased-after-a-while/34584 "2015-11-14T07:20:51Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![ghasem1992](https://avatars.discourse-cdn.com/v4/letter/g/ba8739/32.png) [@ghasem1992](https://discuss.elastic.co/u/ghasem1992)
#### Post date: [November 14, 2015, 7:20am UTC](https://discuss.elastic.co/t/elastic-indexing-rate-decreased-after-a-while/34584/1 "2015-11-14T07:20:51Z")

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I have a problem with bulk indexing rate. As you can see in following graph, after a while the ram usage starts to increse and the indexing rate start to decrese rapidly.  
Why?

 ![](https://us1.discourse-cdn.com/elastic/original/2X/c/cf887969ffbd032208c354df8cdce07af9c89363.JPG)

Server specification:  
CPU: Core i7  
RAM: 12 g

Elastic Configuration:  
Bulk size: 30,000  
ES\_Heap\_Size:5g  
Nodes:1  
Number of shards: 50  
Number of replica: 0  
bootstrap.mlockall: true  
indices.merge.scheduler.max\_thread\_count: 1  
indices.translog.flush\_threshold\_size : 1G  
transient.indices.store.throttle.type : none  
index. compound\_on\_flush: false,  
index. compound\_format: false,  
index. Warmer.enable: false,  
index.refresh\_interval: -1,

Data specification:  
Number of records: 20,000,000

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### Author: ![a.abdi](https://avatars.discourse-cdn.com/v4/letter/a/cab0a1/32.png) [@a.abdi](https://discuss.elastic.co/u/a.abdi)
#### Post date: [November 14, 2015, 4:42pm UTC](https://discuss.elastic.co/t/elastic-indexing-rate-decreased-after-a-while/34584/2 "2015-11-14T16:42:50Z")

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Dear Ghasem,

As you can see in the attached picture, when a merge process starts, the ram usage start to increase too.  
So, the indexing rate decreases rapidly.  
you have to have a look at this [link](https://www.elastic.co/guide/en/elasticsearch/reference/1.4/index-modules-merge.html) for more details.

 ![](https://us1.discourse-cdn.com/elastic/original/2X/8/8bae06bb5ec1c0a1630331aa494f864ed1ea40cb.JPG)

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### 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, 11:38pm UTC](https://discuss.elastic.co/t/elastic-indexing-rate-decreased-after-a-while/34584/3 "2017-07-05T23:38:26Z")

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