CBAS : Cannot retrieve stats on a system under continuous load

Build : 5.0.0-771

On a system that is under continuous load of incoming mutations and queries for a long time, the Analytics stats are shown as 0 or N/A on the UI. Pls see the attached screenshot.

Here is the response from the stats endpoint :
root@ubuntu:~# curl -v 127.0.0.1:8095/analytics/node/stats

• Hostname was NOT found in DNS cache
• Trying 127.0.0.1...
• Connected to 127.0.0.1 (127.0.0.1) port 8095 (#0)
  > GET /analytics/node/stats HTTP/1.1
  > User-Agent: curl/7.35.0
  > Host: 127.0.0.1:8095
  > Accept: /
  >
  < HTTP/1.1 503 Service Unavailable
• no chunk, no close, no size. Assume close to signal end
  <
• Recv failure: Connection reset by peer
• Closing connection 0
  curl: (56) Recv failure: Connection reset by peer