Spot Instances

What it is: Spare EC2 capacity offered at a large discount, but AWS can reclaim it at any time.

What it’s for:

• Fault-tolerant, interruptible workloads (batch processing, CI jobs).
• Big cost savings when interruptions are acceptable.

Key ideas:

• Can be interrupted with short notice.
• Not suitable for critical workloads needing guaranteed availability.

Exam cues:

• “batch jobs that can be stopped and resumed” → Spot.
• “cheapest compute option” → Spot (with interruption tolerance).

Hard words:

• *spare* /sper/: dư thừa
• *reclaim* /rɪˈkleɪm/: thu hồi
• *interruptible* /ˌɪntəˈrʌptəbl/: có thể bị ngắt
• *fault-tolerant* /fɔːlt ˈtɑːlərənt/: chịu lỗi