load_average is not display

[ckylin]

General information

• OS Platform and Distribution (e.g., Linux Ubuntu 16.04):Ubuntu 18.04.3 LTS
• ElasticHQ Version:3.5.4
• Elasticsearch Version:elastticsearch-6.3.1
• Python version (ignore is using docker image): Python 3.6.8
• Browser Vendor and Version (if applicable):

Issue Description

the metric of load_average is not display

Source Code / Logs

web browser console alert attr.js error

Error: <path> attribute d: Expected number, "M0,NaNL399.75833333…".