Flagger Datadog Provider Multiplies Interval by 10x

[GurayCetin]

Problem

When I set a metric interval to 1m, Flagger checks metrics from 10 minutes ago instead of 1 minute ago.
When I set a metric interval to 3m, Flagger checks metrics from 30 minutes ago instead of 3 minutes ago.

Why This Is a Problem

• My canary analysis uses old data instead of recent data
• I can't catch problems quickly because Flagger is looking at old metrics

The Bug in the Code

I found the problem in Flagger's source code. In the file pkg/metrics/providers/datadog.go, there's this line:

datadogFromDeltaMultiplierOnMetricInterval = 10  // ← This is the bug!

This number 10 gets multiplied with my interval setting. So when I set 1m, it becomes 10m.

Here's the code that does it:

// This takes my interval (like "1m") and multiplies it by 10
dd.fromDelta = int64(datadogFromDeltaMultiplierOnMetricInterval * md.Seconds())

The fix is simple: Change that 10 to 1 (or remove the multiplication completely).

Temporary Fix

Right now, I have to set my interval to 1/10th of what I want:

• Want 1 minute? Set 6s
• Want 3 minutes? Set 18s

But this is confusing and hard to remember.

My Setup

• Flagger version: 1.41.0
• Using Datadog provider
• Running on GKE with Istio