Amazon EMR InstanceGroupConfig CloudWatchAlarmDefinition
The CloudWatchAlarmDefinition
property specifies
the conditions that trigger an automatic scaling activity. CloudWatchAlarmDefinition
is a subproperty of the Amazon EMR
InstanceGroupConfig ScalingTrigger property type.
Syntax
JSON
{ "
ComparisonOperator
" :String
, "Dimensions
" : [MetricDimension
, ... ], "EvaluationPeriods
" :Integer
, "MetricName
" :String
, "Namespace
" :String
, "Period
" :Integer
, "Statistic
" :String
, "Threshold
" :Double
, "Unit
" :String
}
YAML
ComparisonOperator
:String
Dimensions
: -MetricDimension
EvaluationPeriods
:Integer
MetricName
:String
Namespace
:String
Period
:Integer
Statistic
:String
Threshold
:Double
Unit
:String
Properties
ComparisonOperator
-
Determines how the metric specified by
MetricName
is compared to the value specified byThreshold
.Valid values:
GREATER_THAN_OR_EQUAL
,GREATER_THAN
,LESS_THAN
, orLESS_THAN_OR_EQUAL
.Required: Yes
Type: String
Dimensions
-
A list of CloudWatch metric dimensions.
Required: No
Type: List of Amazon EMR InstanceGroupConfig MetricDimension
EvaluationPeriods
-
The number of periods, expressed in seconds using the
Period
property, during which the alarm condition must exist before the alarm triggers automatic scaling activity. The default value is 1.Required: No
Type: Integer
MetricName
-
The name of the CloudWatch metric that is watched to determine an alarm condition.
Required: Yes
Type: String
Namespace
-
The namespace for the CloudWatch metric. The default is
AWS/ElasticMapReduce
.Required: No
Type: String
Period
-
The period, in seconds, over which the statistic for applying the metric associated with the alarm is applied. You specify the statistic in the
Statistic
property. CloudWatch metrics for Amazon EMR are emitted every five minutes (300 seconds). If you specify a CloudWatch metric for Amazon EMR, specify 300.Required: Yes
Type: Integer
Statistic
-
The statistic to apply to the metric associated with the alarm. The default is
AVERAGE
.Valid values:
SAMPLE_COUNT
,AVERAGE
,SUM
,MINIMUM
, andMAXIMUM
.Required: No
Type: String
Threshold
-
The value against which the specified statistic is compared.
Required: Yes
Type: Double
Unit
-
The unit of measure associated with the CloudWatch metric being watched. Specify the unit specified in the CloudWatch metric.
For more information, see CloudWatchAlarmDefinition in the Amazon EMR API Reference.
Required: No
Type: String