This function is an alias to fill, with the value parameter set to the metric’s last recorded value displayed within the viewable graph.

last_fill(s("AWS.ELB.HTTPCode_Backend_5XX", "*", {period: "60"}))

In order for last_fill() to work, the metric must have its period attribute set, or you must supply period to the series function.


In the graph below, the metric has many sources which report intermittently:


Here is the same metric with last_fill() applied:

last_fill(s("json.errors.count", "*", {period: "300"}))


The last recorded value within the viewable graph is repeated for the remaining intervals. This function is not recommended to be used with alerts as the last value only applies to the viewable graph, and will not pull the last value of historical data.