Scaling Cooldowns

• A scaling cooldown helps you prevent your Auto Scaling group from launching or terminating additional instances before the effects of previous activities are visible.

• When you use simple scaling, after the Auto Scaling group scales using a simple scaling policy, it waits for a cooldown period to complete before any further scaling activities due to simple scaling policies can start.

Scaling-specific cooldown period

• In addition to specifying the default cooldown period for your Auto Scaling group, you can create cooldowns that apply to a specific simple scaling policy.

• A scaling-specific cooldown period overrides the default cooldown period.

• One common use for a scaling-specific cooldown period is with a scale-in policy.

  • Because this policy terminates instances, EC2 Auto Scaling needs less time to determine whether to terminate additional instances.

    • Terminating instances should be a much quicker operation than launching instances.

      • The default cooldown period of 300 seconds is therefore too long.