AWS bill line item
SpotUsage:m5.large
The hourly running time of an EC2 Spot Instance of the given type. AWS bills it at the Spot market price, which changes, instead of the fixed On-Demand rate.
Spot instance hours
Verified against official AWS documentation last checked
Why it shows up
This line spikes when Spot capacity gets scarce and the market price rises. It also spikes when a workload scales out more Spot capacity. A batch-job burst or an Auto Scaling group set to prefer Spot can do this.
Spot price varies by instance type, AZ, and time. The same fleet size can cost much more from one week to the next with no change in usage volume.
How to cut it
- Diversify across multiple instance types/families and AZs so the fleet draws from a deeper capacity pool instead of one scarce type.
- Use a capacity-optimized allocation strategy to reduce interruption-driven relaunch churn.
- Configure a mixed-instances policy with automatic fallback to a different pool (or On-Demand) instead of retrying the same one.
How to read this code
:instanceType suffixThe specific instance type or size a charge applies to, e.g. BoxUsage:m5.large. One line per distinct type in use.
Source
Source: AWS docs →Found SpotUsage:m5.large on your own bill?
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