KEP-5229: Asynchronous API calls during scheduling #5249
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macsko
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Apr 16, 2025
macsko
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- One-line PR description: Add KEP-5229
- Issue link: Asynchronous API calls during scheduling #5229
- Other comments:
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/cc @dom4ha @sanposhiho I have written some possible approaches to these API calls to start the discussion. I will not be visibly active for the next three weeks, but feel free to comment. |
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| - `nominatedNodeName` scenario support would require more effort in (1.1) or (1.2). | ||
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| #### 2.2: Make the API calls queued |
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I feel like queueing API calls might be a good direction long term and probably won't be that hard to implement.
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| kep-number: 5229 | |||
| alpha: | |||
| approver: "" | |||
| This would require implementing advanced logic for queueing API calls in the kube-scheduler and migrating **all** pod-based API calls done during scheduling to this method, | ||
| potentially including the binding API call. The new component should be able to resolve any conflicts in the incoming API calls as well as parallelize them properly, | ||
| e.g., don't parallelize two updates of the same pod. This requires [making the API calls queued](#22-make-the-api-calls-queued) or | ||
| [sending API calls through a kube-scheduler's cache](#23-send-api-calls-through-a-kube-schedulers-cache) to be implemented. |
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Conceptually what you need here is something pretty similar to DeltaFIFO we use in client-go:
https://github.com/kubernetes/kubernetes/blob/master/staging/src/k8s.io/client-go/tools/cache/delta_fifo.go
We wouldn't operate on object, but on their updates, but that's conceptually exactly what you need:
- tracking changes to a given object all together
- a concept of deduping (if I already scheduled a pod but didn't yet sent the failures, don't send them; if I have multiple failures not yet sent to report, is the last one only valid?, etc.)
| - dom4ha | ||
| - sanposhiho | ||
| approvers: | ||
| - alculquicondor |
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Please change to @dom4ha or @sanposhiho
