A Hidden Cost to Monitoring AWS with 3rd Party Tools
A free trial at Lumigo, Epsagon, DataDog, New Relic or any of them may be costing you tens to thousands of dollars per month.
You might have a free tier or a free trial from a monitoring service. But who’s paying to get the data into that service? You are.
How to tell if your free trial is costing you an arm and a leg
Pulling data via CloudWatch GetMetricData API calls is expensive, not only because of the price of $10.00/million metrics requested, but because your 3rd party service could be requesting this data at a high frequency. Especially in lower environments like Dev or QA, you could get a high volume of GetMetricData (GMD) requests despite few requests to your serverless API in API Gateway.
To see if you have any charges for GMD:
- Go to the AWS Cost Management console’s Cost Explorer
- Filter by Usage Type by:
- typing “gmd”
- clicking “Select All” and then “Apply filters.”
Here’s a screenshot of that filter:
Select the Time Range you want. To get a year, select 1Y and Apply:
You can scroll all the way to the right in the Usage Type table below to see the Usage Type Total and Total cost ($).
Small Serverless Scenario
If you’ve got a few dozen serverless APIs in API Gateway with Lambda, the third party monitoring service may make 10 thousand GetMetricData requests per day. After 365 days, you’ve got a $365 bill for GetMetricData API calls caused by the “free” 3rd party service.
How can I know where the GetMetricData requests are coming from?
You can’t. You’ve got to ask AWS Support to go log diving for you.
So just turn off the monitoring service for an hour or so, if you can get away with that. If there’s a dent in your bill for that hour, then you know it was the monitoring service that’s been making the requests.
Conclusions
Your 3rd party tool may be worth it, because of the saved cost of developing bespoke monitoring solutions. Just take a few minutes to understand how the 3rd party tool affects your AWS bill, not just your bill for that tool.
AWS has 22 native services for Management and Governance. Make sure you’re aware of the options, including the AWS Distro for OpenTelemetry. It even has solutions for Lambda and AWS Managed Service for Prometheus.
And then include the full cost of using monitoring solutions in any comparisons you may make.
