title: Elasticsearch dies on primary node at random times. What should I look for in troubleshooting?
body: <p>I have 2 Elasticsearch VM's running (4 GB RAM VM's) and they are configured in 1 cluster with 2 nodes. It's been running fine for months but all of a sudden in the last week the primary node has been just ending with no reason (that I can find).</p>
  
  <p>So when I try to restart the node it takes a while to re-sync but does so eventually.</p>
  
  <p>I have things set to only use 1/2 the RAM on the server and it seems to be doing that but looking at my free memory and HTOP I'm seeing more than that consumed.</p>
  
  <p>My browser-based plugins (Bigdesk, Marvel, elasticsearch-head) also respond very very slowly now. I have noticed that my marvel index files are massive - over 1 GB a day. Can I remove these to improve performance? The marvel data is way more than my actual index/searchable data.</p>
  
  <p>What else can I do to tweak and optimize this system?</p>
  
  <p>Thanks.</p>