Ask HN: Dashboard tool that displays data along time series?

I am looking for a dead simple dashboard service that displays a chart with data points along a time series. Let me explain: I want to just push the cpu load of my server to this service every minute (via REST or whatever) when i open the dashboard, it display the trend on how the cpu load changed in a nice line chart. I can also drill down to see the exact cpu load in a particular point of time. Replace CPU load with pageviews or whatever. I dont think the metric should really matter. I am not loooking for something complex with bells and whistles like Klipfolio. whats the easiest tool that can do this?