the rolling x window covers the last {span} ms, and the newest of {n} x value(s) is {age}s old, so every mark would be drawn outside the plot. The chart shows its empty state instead. Seed it with data inside the window, widen axis.x.window.span, or drop the window while showing history.

Warnings reference › chart:*:x:window:stale:*

Identifier

chart:*:x:window:stale:*

Raised by

Charts

Since

1.70.0

What happened

A rolling window that no longer reaches the data. Every mark would be drawn far outside the plot, with the axes, the legend and the accessible table all rendering normally, so the chart reads as broken while nothing is wrong with the data. It is asked before anything is dropped, so the readings it counts are exactly the ones the window removes. The key carries the column as well as the chart, so two windows over two columns are two diagnostics.

The fix

Seed the chart with data inside the window, widen axis.x.window.span, or drop the window when showing history. If the message says the readings are stamped *ahead* of the window instead, the producer's clock is wrong - see chart:*:x:window:ahead.

Reference

Covered in full at the API reference.