This flow shows how AWS processes a Spot Instance request, launches it if capacity and price conditions are met, and may terminate it if the spot price rises above your bid.
Execution Sample
AWS
Request Spot Instance withmax price $0.05
AWS checks capacity and current spot price
If capacity available and price <= $0.05, launch instance
Instance runs until spot price > $0.05or terminated
Save costs compared to on-demand instance
This example requests a Spot Instance with a max price and shows how AWS decides to launch or terminate it based on capacity and price.
Process Table
Step
Action
Capacity Available?
Spot Price ($)
Bid Price ($)
Result
Cost Saving
1
Request Spot Instance
N/A
N/A
0.05
Request sent
N/A
2
AWS checks capacity and price
Yes
0.04
0.05
Instance launched
Yes
3
Instance runs
Yes
0.04
0.05
Running
Yes
4
Spot price rises
Yes
0.06
0.05
Instance terminated
Yes
5
Request retry or fallback
Depends
Varies
0.05
Wait or fail
N/A
6
End
N/A
N/A
N/A
Process ends
Cost saved compared to on-demand
💡 Execution stops when instance is terminated due to spot price exceeding bid or capacity unavailable.
Status Tracker
Variable
Start
After Step 2
After Step 3
After Step 4
Final
Capacity Available
N/A
Yes
Yes
Yes
N/A
Spot Price ($)
N/A
0.04
0.04
0.06
N/A
Bid Price ($)
0.05
0.05
0.05
0.05
N/A
Instance State
Requested
Launched
Running
Terminated
N/A
Cost Saving
N/A
Yes
Yes
Yes
Yes
Key Moments - 3 Insights
Why might my Spot Instance request not launch immediately?
If capacity is not available or the current spot price is higher than your bid price, AWS will not launch the instance immediately (see execution_table step 2).
What causes my running Spot Instance to be terminated?
If the spot price rises above your bid price while your instance is running, AWS will terminate it to reclaim capacity (see execution_table step 4).
Do I always save money using Spot Instances?
Yes, Spot Instances cost less than on-demand, but they can be interrupted, so savings come with the risk of termination (see execution_table exit_note).
Visual Quiz - 3 Questions
Test your understanding
Look at the execution_table at step 2, what conditions must be true for the instance to launch?
ACapacity available and spot price less than or equal to bid price
BCapacity unavailable but spot price less than bid price
CCapacity available but spot price higher than bid price
DCapacity unavailable and spot price higher than bid price
💡 Hint
Check columns 'Capacity Available?' and 'Spot Price ($)' vs 'Bid Price ($)' in step 2.
At which step does the Spot Instance get terminated due to price changes?
AStep 3
BStep 4
CStep 5
DStep 6
💡 Hint
Look for 'Instance terminated' in the 'Result' column.
If the bid price was increased to $0.07, how would the termination step change?
AInstance would terminate earlier
BInstance would never terminate
CInstance would terminate later or not at all if price stays below $0.07
DNo change in termination
💡 Hint
Compare 'Spot Price ($)' and 'Bid Price ($)' columns in variable_tracker after step 4.
Concept Snapshot
Spot Instances let you use spare AWS capacity at lower cost.
You bid a max price; AWS launches instance if capacity and price allow.
Instance runs until spot price exceeds your bid or capacity is needed.
You save money but risk instance termination.
Use for flexible, interruptible workloads.
Full Transcript
Spot Instances are a way to save money by using spare AWS capacity. You request an instance with a maximum price you are willing to pay. AWS checks if there is capacity and if the current spot price is below your bid. If yes, your instance launches and runs. If the spot price rises above your bid, AWS terminates your instance. This process helps you save costs compared to on-demand instances but comes with the risk of interruption. The execution table shows each step from request to termination and cost savings.