Threshold exceeded, but aws cloudwatch alarm doesn't work

Hey!

These are few thoughts, you may look into:

• I think you are using 1 second interval, which is frequent, so we can reduce data points.
• As we can see in image, if 3 data points missed in that time period than alarm will be triggered, its rambling around time period and data points, try to alter them. You can use fake process creation app to trigger the alarm in real time.
• make sure the actions are configured properly.
• There could be, alarm was triggered but returned to OK state asap. Due to small time period.

Look into evaluation clearly - Here are the evaluation docs

Hope this help,