2020-07-01 11:03:49 +00:00
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---
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layout: docs
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page_title: Strategy
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sidebar_title: Strategy
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description: Strategy plugins compare the current state of the system against the desired state.
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---
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# Strategy Plugins
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Strategy plugins compare the current state of the system against the desired state
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defined by the operator in the scaling policy and generate an action that will
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bring the system closer to the desired state. In practical terms, strategies
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2020-07-08 22:42:41 +00:00
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receive the current count and a metric value for a task group or from servers in a
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cluster, and output what the new count should be.
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2020-07-01 11:03:49 +00:00
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## Target Value Strategy Plugin
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The target value strategy plugin will perform count calculations in order to keep
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the value resulting from the APM query at or around a specified target.
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### Agent Configuration Options
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```hcl
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strategy "target-value" {
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driver = "target-value"
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}
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```
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### Policy Configuration Options
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```hcl
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check {
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...
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strategy "target-value" {
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target = 20
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threshold = 0.0001
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}
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...
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```
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- `target` `(float: <required>)` - Specifies the metric value the Autscaler
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should try to meet.
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- `threshold` `(float: 0.01)` - Specifies how significant a change in the input
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metric should be considered. Small threshold values can lead to output
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fluctuation.
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