This can be used to dynamically update cloud provider
config (in particular list of managed NodeGroups and their
min/max constraints).
Add GKE implementation.
Function AwsRefFromProviderId call many times. If scale down enable this call default every 10 seconds per each node.
regexp.MustCompile it very heavy function and not need call each time
By caching AWS refs for nodes/EC2 instances already known to be not in any of ASGs managed by cluster-autoscaler(CA).
Please beware of the edge case - this method is safe as long as users don't attach nodes by calling AttachInstances API after CA cached them. I believe, even if it was necessary, a warning in the documentation about the edge case is enough for now. If we really need to support the case, I will submit an another PR to invalidate the cache periodically so that CA can detect the formerly cached nodes are attached to ASG(s).
Also refactor AwsManager for less complexity by extracting types, accordingly to the discussion made [here](https://github.com/kubernetes/autoscaler/pull/46#discussion_r117912687)
This is an alternative implementation of https://github.com/kubernetes/contrib/pull/1982
Notable differences from the original PR are:
* A new flag named `--node-group-auto-discovery` is introduced for opting in to enable the auto-discovery feature.
* For example, specifying `--cloud-provider aws --node-group-auto-discovery asg:tag=k8s.io/cluster-autoscaler/enabled` instructs CA to auto-discover ASGs tagged with `k8s.io/cluster-autoscaler/enabled` to be used as target node groups
* The new code path introduced by this PR is executed only when `node-group-auto-discovery` is specified. There is relatively less chance to break existing features by introducing this change
Resolves https://github.com/kubernetes/contrib/issues/1956
---
Other notes:
* We rely mainly on the `DescribeTags` API rather than `DescribeAutoScalingGroups` so that AWS can filter out unnecessary ASGs which doesn't belong to the k8s cluster, for us.
* If we relied on `DescribeAutoScalingGroups` here, as it doesn't support `Filter`ing, we'd need to iterate over ALL the ASGs available in an AWS account, which isn't desirable due to unnecessary excessive API calls and network usages
* Update cloudprovider/aws/README for the new configuration
* Warn abount invalid combination of flags
according to the review comment https://github.com/kubernetes/autoscaler/pull/11#discussion_r113713138
* Emit a validation error when both --nodes and --node-group-auto-discovery are specified
according to the review comment https://github.com/kubernetes/autoscaler/pull/11#discussion_r113958080
TODO/Possible future improvements before recommending this to everyone:
* Cache the result of an auto-discovery for a configurable period, so that we won't invoke DescribeTags and DescribeAutoScalingGroup APIs too many times
Adds a new optional flag named `configmap` to specify the name of a configmap containing node group specs.
The configmap is polled every `scan-interval` seconds to reconfigure cluster-autoscaler dynamically at runtime.
Example usage:
```
./cluster-autoscaler --v=4 --cloud-provider=aws --skip-nodes-with-local-storage=false --logtostderr --leader-elect=false --configmap=cluster-autoscaler --logtostderr
```
The configmap would look like:
```yaml
kind: ConfigMap
apiVersion: v1
metadata:
name: cluster-autoscaler
namespace: kube-system
data:
settings: |-
{
"nodeGroups": [
{
"minSize": 1,
"maxSize": 2,
"name": "kubeawstest-nodepool1-AutoScaleWorker-1VWD4GAVG35L5"
}
]
}
```
Other notes:
* Make namespace defaults to "kube-system"
according to https://github.com/kubernetes/contrib/pull/2226#discussion_r94144267
* Trigger a full-recreate on a configuration change
according to https://github.com/kubernetes/contrib/pull/2226#issuecomment-269617410
* Introduced `autoscaler/` and moved all the dynamic/recreatable-at-runtime parts of autoscaler into there (Update: the package is now named `core` according to https://github.com/kubernetes/contrib/pull/2226#issuecomment-273071663)
* Extracted the core of CA(=`func Run()` in `main.go`) into `Autoscaler`
* `DynamicAutoscaler` is a wrapper around `Autoscaler` which achieves reconfiguration of CA by recreating an `Autoscaler` instance on a configmap change.
* Moved `scale_down*.go`, `scale_up*.go` and `utils*.go` into the `autoscaler` package accordingly because they seemed to be meant to be collocated in the same package as the core of CA (which is now implemented as `Autoscaler`)
* Moved the `createEventRecorder` func from the `main` package to the `utils/kubernetes` package to make it importable from both `main` and `autoscaler`
Timothy Palpant
Gary Rennie
Michael Nikitochkin
Edward Tsang
mmerrill3
Seth Pollack
Maciej Pytel
Krzysztof Jastrzebski
Marcin Wielgus
Sergey Lanzman
alok87
Joel Speed
Ryan Moore
Ivan Towlson
Seth Pollack
Ryan Walls
Yusuke Kuoka
Johannes Würbach
ejether
Jason Ansel
Phil Kates