Elasticsearch Memory Utilization

Elastic Stack Elasticsearch
1

Hi Team,

I am new to the Elasticsearch world. I had installed the Elasticsearch in one of my lab VM, where it is showing memory utilization is 8.3 GB when I check "systemctl status elasticsearch" and VM gets hang. Is there anyway we can reduce the memory utilization of elasticseach. Please advise.

Thanks,
Debasis

2

Hi,

As far as I know elasticsearch uses Java and the memory is controlled by Java heap size.
You can navigate to elasticsearch -> config -> vm.options and change your heap size.
For example: (you can set your own value)
-Xms1g
-Xmx1g

or

-Xms512m
-Xmx512m

And if you have too many shards (primary or replicas), it will impact your memory usage.
You can disable unnecessary plugins. They also consume memory.

3

Thanks @PodarcisMuralis . Now I can see the memory usage reduces according to the settings in jvm.options file. I tried to curl the IP of my host over 9200 (port is opened and used by elasticsearch process) but giving error as below. Could you please advise

[root@prestovm1 elasticsearch]# curl -X GET "xx.xx.xx.xx:9200"
curl: (52) Empty reply from server

Thanks,
Debasis

4

It seems that elasticsearch is not responding.

I assume you installed curl command and it is working correctly.
Did you restart elasticsearch?

systemctl restart elasticsearch
5

By default, ES use 50% memory. As Podarcis said, set

-Xms2g
-Xmx2g

(without spaces at the begging of line)
in /etc/elasticsearch/jvm.options.d/jvm.options which template you have in /etc/elasticsearch/jvm.options, but do not add to root.

1-2 GB should be fine for learning purpose and not larger indices - few GB. For more info, read the blog .

6

@PodarcisMuralis Yes, curl command working properly and tested also but still the systemctl restart elasticsearch.service does not help me . I am getting same error while doing curl over port "9200".

Thanks,
Debasis

7

@PodarcisMuralis Can you please help me on this.

Thanks,
Debasis

8

I am also out of options here.
If you use many nodes, please check if there is any firewall.
Please check if port 9200 works.

netstat -tulnp | grep 9200

Please check also elasticsearch logs.
var/log/elasticsearch

As a last option, reinstall elasticsearch.

9

Thanks @PodarcisMuralis it works now. Actually I am starting elastic stack due to my interest not sure where to start. Could you please help me.

Thanks,
Debasis