27 lines
977 B
Plaintext
27 lines
977 B
Plaintext
---
|
|
layout: docs
|
|
page_title: Checks
|
|
description: Learn about how the Autoscaler deals with policy checks.
|
|
---
|
|
|
|
# Nomad Autoscaler Check Calculations
|
|
|
|
A scaling policy can include several checks all of which produce a scaling
|
|
suggesting. The checks are executed at the same time during a policy evaluation
|
|
and the results can conflict with each other. In a scenario like this, the
|
|
autoscaler iterates the results the chooses the safest result which results in
|
|
retaining the most capacity of the resource.
|
|
|
|
In a scenario where two checks return different desired directions, the following
|
|
logic is applied.
|
|
|
|
- `ScaleOut and ScaleIn => ScaleOut`
|
|
- `ScaleOut and ScaleNone => ScaleOut`
|
|
- `ScaleIn and ScaleNone => ScaleNone`
|
|
|
|
In situations where the two same actions are suggested, but with different counts the
|
|
following logic is applied, where the count is the absolute desired value.
|
|
|
|
- `ScaleOut(10) and ScaleOut(9) => ScaleOut(10)`
|
|
- `ScaleIn(3) and ScaleIn(4) => ScaleIn(4)`
|