Amazon Elastic MapReduce
API Reference (API Version 2009-03-31)

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An automatic scaling policy for a core instance group or task instance group in an Amazon EMR cluster. An automatic scaling policy defines how an instance group dynamically adds and terminates EC2 instances in response to the value of a CloudWatch metric. See PutAutoScalingPolicy.



The upper and lower EC2 instance limits for an automatic scaling policy. Automatic scaling activity will not cause an instance group to grow above or below these limits.

Type: ScalingConstraints object

Required: Yes


The scale-in and scale-out rules that comprise the automatic scaling policy.

Type: Array of ScalingRule objects

Required: Yes

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following:

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