blog: introducing kube-scheduler-simulator #47104
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| title: "Introducing Kube-scheduler-simulator" | ||
| date: 2024-07-xx | ||
| slug: introducing-kube-scheduler-simulator | ||
| canonicalUrl: https://kubernetes.dev/blog/2024/07/xx/introducing-kube-scheduler-simulator/ |
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What's the reason for including the canonicalURL here? Is this blog mirrored from the k8s.dev site? If so, review comments should be added to the original content there.
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Sorry, actually I just copied those tags from another blog post.
I saw Kwok's blog post, which I actually copied tags from, have an article in each website.
- https://www.kubernetes.dev/blog/2023/03/01/introducing-kwok/
- https://kubernetes.io/blog/2023/03/01/introducing-kwok/
Would you recommend creating a blog post in kubernetes.dev too? What's the general difference between those two blog websites?
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https://www.kubernetes.dev/blog/ is aimed only at people contributing to Kubernetes
https://www.kubernetes.io/blog/ is aimed at people using to Kubernetes
Who is this article aimed at? I think people might be using this even though they are not Kubernetes contributors - right?
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Who is this article aimed at? I think people might be using this even though they are not Kubernetes contributors - right?
Yes, correct. So, here's the place for kubernetes.io blog, right?
Did you suggest making the same post on .dev too? Or, is having it only here fine?
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This article is in the right repo. No need to change it.
We never mirror from the general website to the contributor website, so there's also no need to open a PR against the contributor site for this article.
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updated to use |
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FYI: related issue - #39776 |
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Addressed the points from @nate-double-u. |
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The overall content LGTM. Thanks for the contribution @sanposhiho |
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Fixed. |
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/lgtm |
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We'll need to assign a publication date for this.
Good to know it looks good to publish, but let's ensure the date is right. How about the 22nd of January @sanposhiho ?
/lgtm cancel
because of that concern about a date
/hold
until we have an agreed, future publication date
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@sftim Yes, looks great. I updated the date on the tag. |
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@sftim we missed the date. What's your next suggestion for the publish date? |
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Because it's now marked as a draft |
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| --- | |||
| layout: blog | |||
| title: "Introducing Kube-scheduler-simulator" | |||
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would it be more reader-friendly to use the full name?
| title: "Introducing Kube-scheduler-simulator" | |
| title: "Introducing Kubernetes scheduler simulator" |
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At a minimum, do not upper case the Kube- part as you don't do it in blog text
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| The Kubernetes Scheduler is a crucial control plane component that determines which node a Pod will run on. | ||
| Thus, anyone utilizing Kubernetes relies on the scheduler. |
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| Thus, anyone utilizing Kubernetes relies on the scheduler. | |
| Thus, anyone utilizing Kubernetes relies on a scheduler. |
Why "the" scheduler? There may be customer schedulers as well, right?
| The Kubernetes Scheduler is a crucial control plane component that determines which node a Pod will run on. | ||
| Thus, anyone utilizing Kubernetes relies on the scheduler. | ||
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| The [kube-scheduler-simulator](https://sigs.k8s.io/kube-scheduler-simulator) is a simulator for the Kubernetes scheduler, initially developed by me (Kensei Nakada) as part of [Google Summer of Code 2021](https://summerofcode.withgoogle.com/). |
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| The [kube-scheduler-simulator](https://sigs.k8s.io/kube-scheduler-simulator) is a simulator for the Kubernetes scheduler, initially developed by me (Kensei Nakada) as part of [Google Summer of Code 2021](https://summerofcode.withgoogle.com/). | |
| The [kube-scheduler-simulator](https://sigs.k8s.io/kube-scheduler-simulator) is a simulator for the Kubernetes scheduler, started as a [Google Summer of Code 2021](https://summerofcode.withgoogle.com/) project developed by me (Kensei Nakada) and later received a lot of contributions. |
Also with any GSoC projects it is a good practice to mention the mentor name as well as typically mentor puts a lot of effort into project success. Since it is 3 years past, not sure how important this is.
| The [kube-scheduler-simulator](https://sigs.k8s.io/kube-scheduler-simulator) is a simulator for the Kubernetes scheduler, initially developed by me (Kensei Nakada) as part of [Google Summer of Code 2021](https://summerofcode.withgoogle.com/). | ||
| This tool allows users to closely examine the scheduler’s behavior and decisions. | ||
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| It is useful for casual users who employ scheduling constraints (e.g., inter-Pod affinity) |
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nit: link the https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/#affinity-and-anti-affinity
| It is useful for casual users who employ scheduling constraints (e.g., inter-Pod affinity) | |
| It is useful for casual users who employ scheduling constraints (e.g., [inter-Pod affinity](/docs/concepts/scheduling-eviction/assign-pod-node/#affinity-and-anti-affinity)) |
| Also, testing your scheduler is a complex challenge. | ||
| There are countless patterns of operations executed within a real cluster, making it impractical to anticipate every scenario with a finite number of tests. | ||
| More often than not, bugs are discovered only when the scheduler is deployed in an actual cluster. | ||
| Actually, many bugs are reported by users after we ship the release, and the bugs are found |
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who "we"? tetrate? Maintainers of Kube-scheduler-simulator? Is it an appropriate use of "we" here?
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I mean anyone who develop (custom) schedulers. What would sound the most natural? "you"? or should I say specifically "anyone who develop (custom) schedulers"
| Typically, you will test the scheduler in a small, development cluster before deploying it to production, hoping that no issues arise. | ||
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| [The simulator’s importing feature](https://github.com/kubernetes-sigs/kube-scheduler-simulator/blob/master/simulator/docs/import-cluster-resources.md) | ||
| provides a solution by allowing you to simulate deploying a new scheduler version in a production-like environment without impacting your live workloads. |
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I meant anyone who's using this project. What's the better way?
| [The simulator’s importing feature](https://github.com/kubernetes-sigs/kube-scheduler-simulator/blob/master/simulator/docs/import-cluster-resources.md) | ||
| provides a solution by allowing you to simulate deploying a new scheduler version in a production-like environment without impacting your live workloads. | ||
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| By continuously syncing between your production cluster and the simulator, you can safely test a new scheduler version with the same resources your production cluster handles. |
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Is it referring to the scheduler maintainers? Or customer scheduler developers? Clarify "your" here. Are you suggesting Kubernertes scheduler maintainers to import their test cluster as a test to Kubernetes codebase?
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Same, I mean "you" equals whoever use this project. Whoever use this project can test their custom scheduler with their production cluster's resources.
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| ## Getting started | ||
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| The simulator only requires Docker to be installed on your machine; a Kubernetes cluster is not necessary. |
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how will it access the cluster for the use cases listed above? This is very confusing for me, I do not know what to expect when I run this. If it doesn't need a cluster, what scheduler version will it even use? Which feature gates enabled? Is it compatible with [my cloud] scheduler?
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how will it access the cluster for the use cases listed above?
It internally runs kwok cluster which you can access.
Regarding other points, we don't have compatible matrics or the feature gate control yet, which we have to improve.
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Do you want to refer the article: https://www.cncf.io/blog/2022/08/24/writing-your-own-scheduler-with-kube-scheduler-simulator/? Not sure what is the relashinship here between articles
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I didn't know that article, and I don't want to, honestly.
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| ## Getting involved | ||
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| The scheduler simulator is developed by Kubernetes SIG Scheduling. Your feedback and contributions are welcome! |
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| The scheduler simulator is developed by Kubernetes SIG Scheduling. Your feedback and contributions are welcome! | |
| The scheduler simulator is developed by [Kubernetes SIG Scheduling](https://github.com/kubernetes/community/blob/master/sig-scheduling/README.md#kube-scheduler-simulator). Your feedback and contributions are welcome! |
This PR adds a blog post to introduce sigs/kube-scheduler-simulator.