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huhnmonster

Re:Ask HN: What Are You Working On? (December 2025) on Sunday December 14, 2025 @03:18PM (#46266427)
Working on a single-node job scheduler for Linux. Large HPC clusters use schedulers like SLURM or PBS to manage allocation of resources to users, but these systems are quite overkill when all you have is a single node shared by a few users.

I am trying to offload as much of the complex stuff to existing parts of the kernel, like using systemd/cgroups for resource limiting and UNIX sockets for authentication.

I also use a it this way, but instead I do 90/30 (work/break) as 90 minutes gives me enough time to finish most exercises and tests without having to hurry.

I do around 4 to 5 sessions per day which hits the sweet spot for me as I can endure this for multiple months without having to take days off. This comes at the expense of having to start a few weeks earlier to have enough time to prepare for tests compared to cramming 12 hour days the week before

Re:Ask HN: Where to start for hobby circuit design on Saturday January 30, 2021 @05:18PM (#25973556)
I can tell you what I did, coming from a somewhat similar but different situation. I kind of over-promised for a small project, thinking that some electronics and little code could not possibly be too hard. After some time I realized that if I had to do the stuff around 50 times (project was a small sensor network), I would be stuck soldering for a few weekends. Then decided that maybe learning some ECAD along the way and getting PCBs manufactured would be cool, albeit totally overkill.

I cannot recommend Phil's Lab [1] enough. He has videos which take you from basically an empty sketch to ordering a finished board in around 2.5 to 3 hours. Some of the most worthwhile content I have found on YouTube to date.

Also, get a multimeter and an oscilloscope. Any oscilloscope will do probably, I have one from Amazon for 30$. For my project, it totally does the job, although you may want to invest a bit more here if you intend to use it for more advanced projects. You cannot believe how many times being able to look at a signal has helped me understand where my problem could be and what might be wrong. It has also helped me figure out what questions I had to ask. For simple projects, you are always going to get there by guessing I suppose, but why make it hard on yourself.

Aside from that, just try things. It is probably helpful to spend more time thinking when you are handling more expensive parts, so you do not burn a couple of them out because of carelessness, but also, don't overthink it.

[1]: https://www.youtube.com/c/PhilS94/videos

I guess I understand where you are coming from, but they way I understand it is that RH submits a bulk order for a stock and gets a quote from the MM, which the MM thinks is appropriate. The MM then adjusts its own portfolio accordingly, buying/selling the underlying stock at its own pace.

So, more or less as described, but the order is a little different, right?

Re:Firefox 85 cracks down on supercookies on Wednesday January 27, 2021 @07:30AM (#25927403)
There are also seemingly companies, who just blatantly ignore such regulations.. https://brave.com/google-gdpr-workaround/
I was wondering if someone could explain the countermeasures for such an event. Obviously, as the article states, producers are being shut off in the regions with surplus, while drains, who can afford to shut off, are shut off in the deficit regions.

Is this an automatic process? Or is it more like someone from the company's energy provider calls them and tells them to shut off some devices? And is there not a potential problem, that if too many shut of at once, you now have a surplus again? Or is it coordinated by one single entity?

> In that case it could be interesting to plan for future reinforcements, and continue to run the simulations as time passes and the situation evolves.

While I agree that the idea is good, I imagine that at a point where you are planning to extend your dam by another 20m, you already have to implement the required changes in your foundation and general structure and additionally, turbines and emergency vents have to be upsized for the extended heights. So the only thing you are now missing during build is the extra 20m of dam, as the rest has to be built anyways. This leads back to my initial point of the right amount of over-/underprovisioning..

I am not sure if I understood the second point correctly, but you can obviously tell when a dam becomes too dangerous. This can either be because the foundation has set and you now have increased structural stress, the amount of water has increased beyond the maximum allowed levels or a multitude of other reasons, but they are actively monitored.

This is the question that has been going through my head after I wrote the parent comment.

I have never been in such a situation (at least not one where the stakes were relevant), so take this with a grain of salt. Blaming under these kind of circumstances might arise because the people who do it:

* Either do not have access to the information necessary in order to develop a sufficient understanding of the problem at hand

* Or are incapable of understanding the problem at hand to a sufficient degree (because the project is too big for a single person to grasp or whatever)

So, they resort to assuming some simplifications in order to make everything understandable to them, but these simplifications are likely to be wrong. Consequently, they start blaming people they think to be at fault under their own flawed model of the situation.

A blame-free culture? Explain the situation to such a degree that the decision making around the root cause is easily understandable for everyone. For example, if a bridge fails, there will likely be experts that identify what has caused the failure. If the decision makers for the bridge now say that due to circumstances they disregarded a certain load situation, because x and y and this is an acceptable argumentation (to whoever is judging the situation), there will be less/no blaming as it is now understandable why things have been done that way.

But at a cultural level? I think that this would require everyone to ultimately only judge situations once they have understood the problem at hand. At that point, why do we even talk to each other? Everything we say is based on incomplete information anyways..

Yeah, exactly. The thing is, where do you draw the line of what is statistically so unlikely that you can deem it improbable?

If we run multiple different climate models through some sort of Monte Carlo simulation, I suppose each model would output a different probability of such an event occuring. In the case where all models predict a very low probability, it may be easy to say that it is unlikely. But what if two predict a very low and one predicts a low probability? Is this now applicable and should we build to be able to sustain such an event?

These are hard questions and I currently do not see any way to get better data for the future as the different models still do not agree in many points

How does this manifest in costs? Is it noticeable?

And does rain rate mean the frequency of distinct rain events over hours/days or the intensity of a single rainfall?

Just curious, maybe you can shed some light on this

While I agree with the gist of this, the ones to finally call the shots on such projects are always in a bad spot.

They underprovision and an anomaly happens. Now they are the ones who did everything wrong and should be blamed. The overprovision and nothing ever comes close to the theoretical limit of the structure. Now they have wasted huge amounts of money and again, should obviously be blamed. The easiest way out: Plan exactly to what is considered standard. No one will blame you in either case, even if you know that it is insufficient or stupid.

This is something that will probably hold true in many different industries, the consequences for dams are just a little worse..

Re:Computer Science Curriculum in 1000 YouTube Videos on Tuesday January 12, 2021 @05:01PM (#25754529)
In Germany, we have two different institutions: Universities (identical to US university I guess) and something called Fachhochschule (I don't know if there even is a correct translation for that, lets call it FH).

University is focused on covering the theoretical aspect of computers with a lesser focus on practical applications - although they are thought to some extent - while FH is more focused on building applications and real-life systems with a smaller focus on theoretical aspects.

The only problem is that FH has long been considered second class and everyone wants to attend university. but in my opinion and based on my experience, many people would be a better fit for FH.

For someone deciding whether to attend Uni or FH, it is often not easy because you cannot guess what you are going to do in your work-life and whether you might enjoy research or you would rather go into industry directly.

Aside from that though, I think it is great that we have different institutions for different audiences with differing goals. Does something like that exist in the United States or somewhere else in the world?

This article surprised me since funding came from Softbank and not the state government as most does IIRC.

Where I see the problem with all these forms of energy storage is that there is no one efficient approach (yet!) and innovation will come mostly from government funding, so governments decide what they see as the best opportunity.

This seems like its pretty much hit-or-miss and betting on the wrong thing will arguably speed up the development of it but at the same time, we might end up at a point we could have reached quicker and cheaper had we used a different technology.

There are a bunch of other technologies as well. Huge flywheels [1], which are supposed to be used for very responsive power needs (i.e. grid stabilisation), trains loaded with weights which get pulled up a mountain and released [2], redox-flow batteries and so on.

[1]: https://www.energydigital.com/smart-energy/worlds-largest-fl... [2]: https://aresnorthamerica.com/

Re:Rust is now overall faster than C in benchmarks on Monday January 04, 2021 @03:09AM (#25628780)
Do you think that it may be caused by use of comptime? I have not looked at the benchmark implementations, but that kind of struck me as a reason
Not such a big deal and something rather subjective: Due to Covid, my university started to upload recordings of all of my courses. This has been a godsend for me, as I did not attend lectures previously and now have the chance to watch them only when needed.

Also, where before I often had to go to campus for 1.5hrs, which often meant sitting in train for equally long. Now, I can watch stuff from home and don't have to waste time travelling.

Out of curiosity I just did what you described - to me it seems like machine learning and everything surrounding it is the only hot topic right now.

Would you agree or did I just look at the wrong Github accounts?

Re:Ask HN: Is anyone working on anti-drone tech? on Monday December 21, 2020 @03:43PM (#25499329)
While this is likely not low cost, the Anvil[0] seems to be a reusable intercept drone. I have yet to see it in action, but I could imagine it looks pretty cool.

I heard that the company is pretty controversial, but I find their tech to be very cool nevertheless.

[0]: https://www.anduril.com/

Re:Starship – SN8 – High-Altitude Flight Test on Wednesday December 09, 2020 @06:06PM (#25366662)
At around 1:54:50, upon full landing thrust, the exhaust flames turn green. I know colored flames from chemistry classes, but I always assumed that was caused by certain salts.

Rocket fuel, to my knowledge, does not contain any of those ingredients. Can someone explain what happened there? Was this planned?

This has been done in my last exam phase and has worked well. They cranked the AC to 11, which made it quite an unpleasant envirommemt, but I would rather wear a jacket than take online exams
That is, well..., rather bad. I imagine if this trend prevails in the future, we will see your plumber asking you if he can charge his transporter and deducting their charging cost from your invoice.
Re:Ableton Live 11 on Wednesday November 11, 2020 @04:35PM (#25063302)
It is not only the analogy. I like to use Midi controllers which have hardware knobs mapped to software knobs for live performances.

Sure, you could map a knob to a slider or anything really, but it makes the interaction easier

Re:Ask HN: What do you keep learning and forgetting about? on Monday October 19, 2020 @04:39AM (#24824358)
Calculus. The basics and ways of thinking stick quite well, but specific execution of some algorithms escape my head as soon as I don't use them anymore. I guess that's just the way learning at uni works though

Ask HN: Tips for citizen dev's and non-software professionals

This might be a controversial topic with very different opinions, but what are some tips and trick for people who write code in a work setting, but are not trained software professionals?To give an example: I wrote a lot of automation for a bunch of analysis that run on a daily/weekly basis. I always try to do as much as possible in our data warehouse, but some things just cannot be done there,...

( Read More... | 1 comment | on HN )
Re:Hash Array Mapped Tries (HAMT) to the Rescue on Monday September 07, 2020 @10:13AM (#24399528)
Can someone explain the reasoning for using a HAMT here? I have played around with hashtables quite a bit, but altough HAMT's are cool and a lot more memory efficient, they are likely not faster and will at some point suffer from more severe memory fragmentation than hashtables.

Is the concern speed or memory? Because speed would kind of seem strange, since after changing to the new architecture, they should see a strong decrease in messages being exchanged anyways, right?

Or are go's maps inefficient? Genuinely curious

Re:Ask HN: What do you use Google Sheet or Excel for? on Monday August 24, 2020 @05:47PM (#24265931)
This. The stuff I am working on is mostly glorified ETL. Some sheets of course are user facing and will have a nice sheet inside the workbook where everything is summed up.

Generally it looks like this:

1. Get data from a central source (data warehouse/other departments)

2. Transform/combine different sources etc. (mostly with pivot tables)

3. output to a sheet

4. add some sort of automation so it runs on its own the next time

Disclaimer: I am a working student ("part-time" intern in Germany, more or less), should not make any difference though.

Recurring meetings: This might be more personal preference, but I personally would go for scheduled meetings. Every day might be overkill though. Depending on the size of tasks, every other day will probably be just fine. Many questions will likely come up once actually doing work, so be somewhat available to answer them.

Growth: This is probably a lot harder to do remotely, and also largely depends on the previous experience of your intern. One important thing my mentor taught me early on was how to scope tasks, ask the right questions and when to say no to something.

When someone would ask me to do some report, I would always just do it and not question what exactly I was doing (Because for the most part, I did not really know). It turned out that often times the people asking me for it missed something that I had noticed right away but was afraid to ask. I would end up doing the report twice then.

This obviously comes with experience and once you feel comfortable with the systems used etc., but once you feel your intern knows their way around, encourage them to be critical of requests and always ask questions if they notice something that might be off.

Feedback: I would strongly suggest you do so. But also ask him/her, if he/she would like feedback. This also ties in with the growth aspect. You will need the first few weeks to identify strengths and weaknesses and once you notice a recurring theme, that is something you can give feedback on.

Personal example: I was always trying to finish my tasks quickly and more often than not there were subtle mistakes in there, which were always super trivial to fix, but they were there. In my first feedback session, my mentor told me that he was absolutely astounded by my speed, but would rather have me take more time and be sure to do it correctly than rush it. This is obvious in hindsight, but especially if you want to prove yourself, it might not be clear whether it is better to be fast or correct.

Some general things: - Try to integrate your intern into your daily work life as much as you can. What I especially enjoyed was my mentor asking me questions about a task he had and was not sure how to proceed with it. Even if you do not get useful input at first, it helps your intern feel like actually doing useful work. And at one point he will likely be able to provide actual useful input to your day to day work, so its a win-win.

- This is often unavoidable, but please try to give him/her actual work, not something like "Sort these folders by ascending date" or "Print out 50 pdf's and send them to customers". This depends on whether your intern got hired for a certain project or just a general internship though.

Ask HN: How to value time more than money/fame?

During quarantine I have made an important discovery about myself: Everything I do is somehow related to begin 'productive' or with the goal of me receiving praise for it in whatever way. Espeically now with more free time at hand (which I was initially planning to use for something 'productive or useful'), I just ended up wasting about half of it since I deemed the things I was doing...

( Read More... | 1 comment | on HN )
I totally agree with you there, I was arguing from the view of a bad actor, not necessarily a government.

For a bad actor, the cost-reward looks pretty low (if we assume a high initial investment like a couple hundred million dollars to approach our goal of data collection in a shorter timeframe), but for a government that is probably totally doable.

Going from what currently seems to be popular: huge botnets that carefully try to curate "real" users from random accounts. Rolling your own (Network that is, like FB or TikTok) seems pretty unlikely regarding initial investments, user base etc.

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