Managed Service for Prometheus charges for metric data ingestion based on one of two methods. The right choice depends on how many labels your metrics carry -- choosing the wrong method can significantly increase costs for high-cardinality workloads.
Billing methods
| Method | How it works | Best for |
|---|---|---|
| By remote write metric data size | Charges based on the size of uncompressed metric data sent to your Prometheus instance | Metrics with few labels per time series |
| By metric sample count | Charges based on the number of data points sent to your Prometheus instance | Metrics with many labels per time series |
How labels affect cost
Each unique combination of label values creates a separate time series. More labels mean more time series, which increases the uncompressed data size relative to the number of samples.
Under billing by data size, more time series generate a larger payload because the label metadata is repeated in each series. Under billing by sample count, you are charged based on the number of data points, regardless of label size.
Set the billing method for a new instance
Log on to the Prometheus console. In the left-side navigation pane, click Instances.
Click Create Prometheus Instance. In the panel that appears, select a billing method. To apply this method as the default for future instances, enable the default setting option.
Change the billing method for an existing instance
The new billing method takes effect immediately. All charges from that day onward are calculated based on the new method.
The billing method can only be changed once per instance. Before switching, verify which method better fits your current metric structure.
Log on to the Prometheus console. In the left-side navigation pane, click Instances.
Find the target instance and click Settings in the Actions column. In the panel that appears, click the edit icon
next to the billing method.
In the dialog box, select the other billing method and click OK.
FAQ
How do I determine which method is cheaper for my workload?
Compare the average number of labels per metric in your workload. If most metrics carry many labels with high cardinality values (such as unique request IDs, user IDs, or IP addresses), billing by sample count is typically more cost-effective. If your metrics use a small, fixed set of labels, billing by data size is usually cheaper.
What happens to my existing charges when I switch methods?
The switch takes effect immediately. Charges before the switch date remain calculated under the original method. From the switch date onward, all charges use the new method.
Can I switch the billing method more than once?
No. Each instance allows only one billing method change. Choose carefully before switching.