AWS SysOps Course Summary: Burstable Performance Instances

Overview of Burstable Performance Instances (T2/T3)

• Burstable Performance Instances: Instances in the T-family (e.g., T2, T3) provide a baseline level of CPU performance with the ability to burst above the baseline.
• CPU Credits: These instances accumulate CPU credits when running below the baseline level, which can be spent to burst above the baseline when needed.
• Credit Balance: If the instance exhausts its CPU credit balance, CPU performance will degrade significantly.
• Monitoring: AWS CloudWatch can be used to monitor CPU utilization and credit balance.

CPU Credits and Performance

• Accumulation: CPU credits are accumulated over time and are used when the instance bursts.
• Baseline Performance: When credits are exhausted, the CPU utilization drops to the baseline performance level.
• Instance Types: Different T-family instances earn credits at different rates and have different maximum credit balances.

Example: T2 Micro Instance

• Launch Credits: 30 credits are provided on launch.
• Credit Earning Rate: 6 credits per hour.
• Maximum Credits: 144 credits.
• Baseline Performance: 10% of CPU utilization.

Experiment: CPU Stress Test on T2 Micro

• Stress Command: Running a CPU stress command can cause CPU utilization to spike to 100%.
• Credit Usage: During high CPU utilization, the credit balance decreases.
• Performance Drop: Once credits are depleted, CPU utilization drops to the baseline level (10% in this case).