For scaling deployments in particular, use a direct object get rather than the /scale API #1458
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… than the /scale API so that it can use the informer cache for better performance. This is annoying as a special case but is so common and improves performance so much that I think it's worthwhile to include. Another option would be to majorly increase the QPS rate limit on the scaling API client however that would also increase kube-apiserver load while watches/informers are generally much less impactful. Signed-off-by: Noah Kantrowitz <noah@coderanger.net>
Signed-off-by: Noah Kantrowitz <noah@coderanger.net>
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Also adds support for StatefulSets for symmetry. Signed-off-by: Noah Kantrowitz <noah@coderanger.net>
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| switch { | ||
| case targetGVKR.Group == "apps" && targetGVKR.Kind == "Deployment": | ||
| deployment := &appsv1.Deployment{} | ||
| err := e.client.Get(ctx, client.ObjectKey{Name: targetGVKR.Resource, Namespace: scaledObject.Namespace}, deployment) |
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targetName := scaledObject.Spec.ScaleTargetRef.Name...
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| err := e.client.Get(ctx, client.ObjectKey{Name: targetGVKR.Resource, Namespace: scaledObject.Namespace}, deployment) | |
| err := e.client.Get(ctx, client.ObjectKey{Name: targetName, Namespace: scaledObject.Namespace}, deployment) |
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Seems weird to use different data sources, increased chance of them being out of sync?
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ScaledObject and the target workload should be always in the sync (the same namespace, if you are asking for this). But in your original code, I don't understand the intention, how do you want to guess the name from targetGVKR.Resource?
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I completely misunderstood this code, you are correct :)
| currentReplicas = *deployment.Spec.Replicas | ||
| case targetGVKR.Group == "apps" && targetGVKR.Kind == "StatefulSet": | ||
| statefulSet := &appsv1.StatefulSet{} | ||
| err := e.client.Get(ctx, client.ObjectKey{Name: targetGVKR.Resource, Namespace: scaledObject.Namespace}, statefulSet) |
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targetName := scaledObject.Spec.ScaleTargetRef.Name...
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| err := e.client.Get(ctx, client.ObjectKey{Name: targetGVKR.Resource, Namespace: scaledObject.Namespace}, statefulSet) | |
| err := e.client.Get(ctx, client.ObjectKey{Name: targetName, Namespace: scaledObject.Namespace}, statefulSet) |
Co-authored-by: Zbynek Roubalik <726523+zroubalik@users.noreply.github.com> Signed-off-by: Noah Kantrowitz <noah@coderanger.net>
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Co-authored-by: Zbynek Roubalik <726523+zroubalik@users.noreply.github.com> Signed-off-by: Noah Kantrowitz <noah@coderanger.net>
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… than the /scale API (kedacore#1458) * For scaling deployments in particular, use a direct object get rather than the /scale API so that it can use the informer cache for better performance. This is annoying as a special case but is so common and improves performance so much that I think it's worthwhile to include. Another option would be to majorly increase the QPS rate limit on the scaling API client however that would also increase kube-apiserver load while watches/informers are generally much less impactful. Signed-off-by: Noah Kantrowitz <noah@coderanger.net> * Update changelog. Signed-off-by: Noah Kantrowitz <noah@coderanger.net> * Use the already-normalized GVKR data so less weird string parsing. Also adds support for StatefulSets for symmetry. Signed-off-by: Noah Kantrowitz <noah@coderanger.net> * Apply suggestions from code review Co-authored-by: Zbynek Roubalik <726523+zroubalik@users.noreply.github.com> Signed-off-by: Noah Kantrowitz <noah@coderanger.net> * Apply suggestions from code review Co-authored-by: Zbynek Roubalik <726523+zroubalik@users.noreply.github.com> Signed-off-by: Noah Kantrowitz <noah@coderanger.net>
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So that it can use the informer cache for better performance.
This is annoying as a special case but is so common and improves performance so much that I think it's worthwhile to include. Another option would be to majorly increase the QPS rate limit on the scaling API client however that would also increase kube-apiserver load while watches/informers are generally much less impactful.
Checklist
Refs #1449