The mechanism of unregistered nodes removal is not the first
responsibility of Cluster Autoscaler. We do not want to renderi CA
unsable (disable scale-up and scale-down) if removing unregistered nodes
cannot be done for prolonged period of time.
We need to call refresh before getNodeInfosForGroups. If we have
stale state getNodeInfosForGroups may fail and we will end up in infinite crash looping.
filterOutSchedulableByPacking is an alternative to the older
filterOutSchedulable. filterOutSchedulableByPacking sorts pods in
unschedulableCandidates by priority and filters out pods that can be
scheduled on free capacity on existing nodes. It uses a basic packing
approach to do this. Pods with nominatedNodeName set are always
filtered out.
filterOutSchedulableByPacking is set to be used by default, but, this
can be toggled off by setting filter-out-schedulable-pods-uses-packing
flag to false, which would then activate the older and more lenient
filterOutSchedulable(now called filterOutSchedulableSimple).
Added test cases for both methods.
Replace the simple boolean ScaledUp property of ScaleUpStatus with a more
comprehensive ScaleUpResult. Add more possible values to ScaleDownResult.
Refactor the processors execution so that they are always executed every
iteration, even if RunOnce exits earlier.
- This is intended to address the issue described in https://github.com/kubernetes/autoscaler/issues/923
- the delay is configurable via a CLI option
- in production (on AWS) we set this to a value of 2m
- the delay could possibly be set as low as 30s and still be effective depending on your workload and environment
- the default of 0 for the CLI option results in no change to the CA's behavior from defaults.
Change-Id: I7e3f36bb48641faaf8a392cca01a12b07fb0ee35
No change in actual logic being executed. Added a new
NodeGroupListProcessor interface to encapsulate the existing logic.
Moved PodListProcessor and refactor how it's passed around
to make it consistent and easy to add similar interfaces.
AutoscalingContext is basically a configuration and few static helpers
and API handles.
ClusterStateRegistry is state and thus moved to other state-keeping
objects.
t-qini
Pengfei Ni
silenceper
Vivek Bagade
Łukasz Osipiuk
Jakub Tużnik
Krzysztof Jastrzebski
Kubernetes Prow Robot
Chris Bradfield
Jiaxin Shan
Aleksandra Malinowska
Uday Ruddarraju
Jacek Kaniuk
Maciej Pytel
Thomas Hartland
Steve Scaffidi
Beata Skiba
Karol Gołąb