Native memory leak with olt plugin

in our cluster we use olt plugin version 7.8.1. Open distro version is

We are observing native memory growth as below.

Steps to reproduce:

  • Create a simple index
curl -H "Content-type: application/json" -X PUT --insecure https://localhost:9200/test1 -d '{
      "number_of_shards": 1  
        { "field1": { "type": "text" }  }  
  • In loop update any setting of it

for ((i=1;i<=100;i++))
    curl -H "Content-type: application/json" -X PUT --insecure https://locahost:9200/test1/_settings -d '{
      "settings": {
        "index.unassigned.node_left.delayed_timeout": "5m"
  • Monitor the process memory using top or ps command
    RSS memory keeps increasing. It never releases. For every index creation/setting update memory increases by 1MB.
    So above loop of 100 create a leak of 100MB.

  • How did we relate this leak to OLT plugin?
    removed the plugin and ran the same loop. We don’t see any increase in memory.