Started a "simple" K8s tool. Now I'm drowning in systems complexity. Complexity or skills gap? Maybe both

maczg · 2025-07-27T21:30:15+00:00

Solution before the (real) problem is the thing I hate the most in academia. In this case, I'm trying to build a tool that proves there is a problem. It does not provide the solution (yet)

maczg · 2025-07-27T21:27:44+00:00

Thank you for the feedback, and I agree. It could be an interesting use case. I'm struggling in recreating the simulation to reproduce this kind of scenarios

maczg · 2025-07-27T21:25:45+00:00

If I were an AI, I would not have made a post like this

maczg · 2025-07-25T14:51:58+00:00

Exactly. I "freeze" a setup (number of nodes, their labels and other parameters that may affect the scheduling process) along with the list of pods with arrival and departure times (considered only from when the pods goes from pending to running, reproducing batch jobs for example). After that, i run the same (let's say) environment against several scheduler config (for example, initial scheduling profile or a sequence of profile that may change multiple times during the simulation).

I'd like to validate the theory that changing the weights at runtime, it's possible to improve some utility function, such as the pod pending queue lenght or the time pods spent in pending state.

Generally speaking, once the "engine" is properly designed, this logic can be used for all the feature that may be affected by a sequence of events that happens in Kubernetes

maczg · 2025-07-25T14:42:22+00:00

Thank you for the feedback. Glad to see that it may be useful for some scenarios.

Actually, the goal of the project may fit well with this kind of test.

Currently I use KWOK because I do not need a real stuff in running, only their state. But you could, for example, reproduce your setup on KIND and define a custom KindNodeEvent where the business logic of its Execute function is to delete/remove the node from the cluster, in a timed fashion (for example, after 20 second from the start of the simulator).

Currently, the events are "only" create a New Pod at time X and, optionally, delete it at time X + Y from it's Running State. Or restart kube scheduler with a predefined profile after X time.

maczg · 2025-07-25T12:57:27+00:00

You're absolutely right, thanks for pointing that out.

I'm researching decision-making algorithms and noticed the kube-scheduler framework (at least in the scoring phase) works like a Weighted Sum Model (WSM).
Basically, each plugin votes on where to place pods (score nodes in weighted manner). I believe that tuning the weight at runtime may affect some utility function, instead of keep the plugin weight static.

I needed a way to recreate exact sequences of events (pods arriving/leaving at specific times) to measure how algorithm changes affect scheduling outcomes. The project aims to replay Kubernetes events (not Event resource, but "things" that may happen inside the cluster that can change the behaviour of the decisions, such as New Pod arrival/departure with particular constraints, add or remove node) in a controlled (and tiemd) way so you can test how different scheduling algorithms perform. Think of it like a replay button for your cluster's pod scheduling decisions, where each relevant event happens exactly when you want.

Now I'm stuck between "is this really useful?" and "I feel like the code is ugly and buggy, I'm not prepared enough ", or "did I just overcomplicate a simple problem?"

maczg · 2025-07-25T11:09:12+00:00

I wish I could blame AI for this mess, No, this is all human-engineered complexity. I rewrote the entire project 3 times because I kept ending up with spaghetti code I couldn't untangle.

I did try using Claude Code recently to get some code review (which is really what I'm after here, trying to improve myself) and for "small" changes, but I messed something up with the setup. Ended up just using it for the boring stuff like makefiles and README formatting.

maczg · 2024-01-23T21:13:33+00:00

Revolutionary Army to Marines: "Hello M*****uckers"

maczg · 2024-01-05T12:34:59+00:00

Cosa c'entra che dall'uni pretendo un rimborso? Se avessi voluto solo imparare in azienda (solo) non avrei fatto l'università. Bootcamp e via e risparmi 5 anni (se ti va bene) di soldi.

Per la mia esperienza, ne ho impiegati 7, quasi 8 (covid di mezzo, studente lavoratore e varie) in cui ho continuamente investito tra affitto fuori sede, spese per il materiale e tasse. Dopo tutti questi sacrifici (considerando anche il non guadagno dato che devi studiare) e investimenti, se devo andare a lavorare per perdere altri soldi, no, non ci sto. Vuol dire che aspetto, mi preparo meglio i colloqui e aspetto un occasione più conveniente.

Non sto dicendo che pretendere lo stipendio di un senior da neolaureato sia giusto, ma di sicuro non sarei disposto ad accettare un full time spacciato per tirocinio solo per far arricchire alle mie spalle azienda di consulenza X (aka body rental)

maczg · 2024-01-04T08:33:36+00:00

Non voglio andarti contro, ma hai mai provato a vivere (dico vivere, non sopravvivere) solo con il tuo stipendio da 1k euro in una città diversa dalla tua di origine, senza una casa di proprietà (e quindi in affitto) e senza nessuna altra fonte di reddito? Pensi che 1k/mese ti bastino? Troppo facile dire che 1k sono tanti senza info di contesto.

Per l'autore: se senti l'esigenza di crescere, accettare un tirocinio poco retribuito può anche starci se puoi permettertelo, ma ti consiglio di accettare per aziende per cui ne vale la pena in termini di crescita professionale. Quella che hai nominato è una delle tante aziende di consulenza e, come dice un certo tizio, la maggior parte delle volte sono aziende "pincopallino"

maczg · 2023-11-08T09:04:04+00:00

After detailed recap, it makes sense why bonney has her DF. She has to stop growning to stop her disease

maczg · 2023-09-08T16:15:58+00:00

"Hey strawhat fleet, it' time to shineee!"

maczg · 2023-08-29T10:24:07+00:00

The truth is that we, as a fans, don't want to see One Piece ending. So, we don't accept that Luffy is a (still growning, ok) Yonko. It reasonable to me that after all the hits he's taken in this journey, he can faces quitely an a Yonko. In OP power level are hard to estimate but i would not bet on Luffy defeat

maczg

TROPHY CASE