CloudWatchAlarmDefinition - Amazon EMR
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CloudWatchAlarmDefinition

The definition of a CloudWatch metric alarm, which determines when an automatic scaling activity is triggered. When the defined alarm conditions are satisfied, scaling activity begins.

Contents

ComparisonOperator

Determines how the metric specified by MetricName is compared to the value specified by Threshold.

Type: String

Valid Values: GREATER_THAN_OR_EQUAL | GREATER_THAN | LESS_THAN | LESS_THAN_OR_EQUAL

Required: Yes

MetricName

The name of the CloudWatch metric that is watched to determine an alarm condition.

Type: String

Required: Yes

Period

The period, in seconds, over which the statistic is applied. CloudWatch metrics for Amazon EMR are emitted every five minutes (300 seconds), so if you specify a CloudWatch metric, specify 300.

Type: Integer

Required: Yes

Threshold

The value against which the specified statistic is compared.

Type: Double

Valid Range: Minimum value of 0.0.

Required: Yes

Dimensions

A CloudWatch metric dimension.

Type: Array of MetricDimension objects

Required: No

EvaluationPeriods

The number of periods, in five-minute increments, during which the alarm condition must exist before the alarm triggers automatic scaling activity. The default value is 1.

Type: Integer

Required: No

Namespace

The namespace for the CloudWatch metric. The default is AWS/ElasticMapReduce.

Type: String

Required: No

Statistic

The statistic to apply to the metric associated with the alarm. The default is AVERAGE.

Type: String

Valid Values: SAMPLE_COUNT | AVERAGE | SUM | MINIMUM | MAXIMUM

Required: No

Unit

The unit of measure associated with the CloudWatch metric being watched. The value specified for Unit must correspond to the units specified in the CloudWatch metric.

Type: String

Valid Values: NONE | SECONDS | MICRO_SECONDS | MILLI_SECONDS | BYTES | KILO_BYTES | MEGA_BYTES | GIGA_BYTES | TERA_BYTES | BITS | KILO_BITS | MEGA_BITS | GIGA_BITS | TERA_BITS | PERCENT | COUNT | BYTES_PER_SECOND | KILO_BYTES_PER_SECOND | MEGA_BYTES_PER_SECOND | GIGA_BYTES_PER_SECOND | TERA_BYTES_PER_SECOND | BITS_PER_SECOND | KILO_BITS_PER_SECOND | MEGA_BITS_PER_SECOND | GIGA_BITS_PER_SECOND | TERA_BITS_PER_SECOND | COUNT_PER_SECOND

Required: No

See Also

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