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I built and debugged an embedded stub loader for Rp2350 to program MRAM and validate hardware status for a satellite. About 2.5 hours of my time, a lot of it while supervising students/doing other things.

This would have been a couple day+ unpleasant task before; possibly more. I had been putting it off because scouring datasheets and register maps and startup behavior is not fun.

It didn’t know how to troubleshoot the startup successfully itself, though. I had to advise it on a debugging strategy with sentinel values to bisect. But then once explained it fixed the defects and succeeded.

LLMs struggle in large codebases and the benefit is much smaller now. But that capability is growing fast, and not everything software developers do is large.


> The liquid-cooled AI racks being used today for training and inference workloads almost certainly have far higher power output than that.

75kW is a sane "default baseline" and you can find plenty of deployments at 130kW.

There's talk of pushing to 240kW and beyond...


What's the alternative, though? Removable panels will be more expensive, and troublesome in various ways.

Drywall is not too bad to deal with. And 99% of the wall surface doesn't need to be opened for a -long- time.


I watched a video recently, which I can't find, where an architect set up a beautiful wooden baseboard around the entirety of their property, and that baseboard held all mechanicals and was perfectly clean and easy to get into as needed.

Drywall is manageable and cheap, I agree. But it's more painful than it should be for something that _will_ require maintenance.


I've seen videos where people will put in removable drywall panels that can just be lifted out for access.

There are a lot of downsides though. You lose airsealing, if you don't have an airtight building envelope on the outside of the drywall. You lose fire resistance. You often lose aesthetics, although I've seen this done extremely tastefully. You lose childproofing, and run the risk of a kid electrocuting themselves or destroying your plumbing or dropping stuff in the wall. You impose constraints on what can go on the walls and where your furniture can go.

Given that drywall is pretty easy to cut and replace, most people figure it's just not worth the costs for something you do infrequently.


This sounds great but violates all the building codes for a variety of reasons: eddy currents, risk of electrocution if there’s a short somewhere, noise in telecom cables, etc.

You can absolutely put NM cable, etc, under a cover. It's just more trouble than it is worth. You still need the required setbacks from the wall, etc, and .. there's reasons why bored holes very low on the wall (like for a baseboard cover) could be problematic.

And for telecom / low voltage, you have a lot of freedom of how you do it.


Mass production should be able to make this standard. Walls don't vary that much.

Personally I've been printing snap in access panels whenever I have to get into a wall these days - in white PETG they pretty much disappear into the wall for me.


Odds are you are compromising the fire safety of your residence by doing this.

He was a top 10 20th century physicist-- and the 20th century was full of rock stars-- and a Nobel Laureate. He also did more interesting work outside his core domain than you'd expect; the cooperation with Thinking Machines, the Rogers Commission, early use of computers as an instrument, institutional/advisory roles, etc.

I think anyone who has read his narratives realizes the dude had some personal flaws.


Yah. He didn't write the Feynman Lectures on Physics. He just came up with the unique arguments in them and gave the lectures at Caltech; it fell to Leighton and Sands to do most of the work of knitting it into a cohesive, coherent book.

And his other books-- they're just his stories, trying to capture the characteristic style in which he talked, while editing it to be a cohesive written work.

This criticism is maybe valid for QED-- I am not sure what fraction of that he was really involved in-- but not the rest of his body of work. Is this supposed to be bad?


Do you mean he didn’t write the lectures he gave to students? I know the books weren’t put together by him and were substantially edited, but I thought the original lectures as delivered by him were either all or largely his work.

I once worked through part of the first volume of his lectures in the published book while listening to the recordings of him partly out of curiosity to see how much the original lectures as he gave them matched the ones which were compiled and published in written form (which I already knew was something not done by him). I came away feeling impressed one could either stick so closely to some lecture notes when lecturing and/or put together a written work which so closely matched a spoken one without coming across as being a transcript. It’s quite the accomplishment and one which I felt was a credit to everyone involved.


Yah, I was saying the volumes.

> put together a written work which so closely matched a spoken one without coming across as being a transcript.

Leighton deserves the credit for this. Feynman did share his notes, but Feynman's notes are.. an adventure.. to work through.


> Leighton deserves the credit for this. Feynman did share his notes, but Feynman's notes are.. an adventure.. to work through.

It's pretty clear he also used the recordings of the lectures themselves. Otherwise there'd be a much bigger difference between the lectures as presented in the books and the audio recordings[1] of him actually giving the lectures. Leighton deserves a lot of credit, but the lectures Feynman gave were substantially similar enough that it's absurd not to act as though he didn't co-author them.

> Feynman did share his notes, but Feynman's notes are.. an adventure.. to work through.

I don't doubt his notes would be, however they also used the audio recordings of and took notes during the lectures themselves for the books. I'm not sure how much they relied on Feynman's notes themselves though. It's been about 15 years since I last read and listened to them together, but I recall the experience of the combined activity being that the book was surprisingly close to being a transcript of what he said (including references to figures which the books reproduced).

This is why I thought it was impressive that the book didn't read like a transcript on its own. I rarely encountered professors who gave such well-structured lectures, but it seems like something Feynman could not only give prepared lectures in this way, but could do this off the cuff as well.

[1] https://www.feynmanlectures.caltech.edu/flptapes.html


> Leighton deserves a lot of credit, but the lectures Feynman gave were substantially similar enough that it's absurd not to act as though he didn't co-author them

I'm sorry that it's difficult to convey tone on the internet. My intent was to highlight that absurdity that seemed to be present in the comment that I replied to-- Feynman only came up with the physics and gave the lectures, but didn't actually "write the book" is not much of a gotcha as far as the accomplishment goes.

It doesn't take away from Feynman, but it maybe adds a lot to each of the Leightons that they could capture such a range of ideas and Feynman's tone so well without simply repeating things verbatim in that transcript style.

> (including references to figures which the books reproduced).

Yes, this is one of the areas of significant challenges in reproduction. So Leighton definitely deserves a whole lot of respect for producing the work, from audio recordings, a few spare photographs, and notes. Even more impressive is what the Goodsteins did with the "Lost Lecture" to recreate the figures from just a few pages of surviving notes that looked like this:

https://i.imgur.com/zQessy9.png

(And it seems Feynman gave this 60 minute lecture quickly wandering between history, geometrical ideas, and dynamics-- that still seems well organized-- with these few pages of sparse notes).


No worries! That makes sense. I got tripped up by "just came up with the unique arguments [...] and gave the lectures" and "Leighton and Sands [did] most of the work of knitting it into a cohesive, coherent book". It felt like glossing over the degree to which the books' contents match the words he spoke.

> Yes, this is one of the areas of significant challenges in reproduction.

I feel this deeply. I'm very slow at writing by hand and have trouble paying attention to what someone's saying if I'm also trying to simultaneously summarize it. In college I solved this by becoming very, very swift with LaTeX. My pure math notes were easiest, but I struggled with physics notes the most. I settled on a middle ground of learning TikZ and making a bunch of LaTeX macros for common stuff. This did well enough for most simple diagrams. I'd fall back to hand-copying more complicated ones and just typing the text. I'd either scan the drawings afterward and add annotations as needed or convert fully into LaTeX. Converting these hand-drawn ones into LaTeX was a ton of work. After doing this for a short bit, I realized that I was remembering the more complicated diagrams better than the easier ones. I figured out that being able to take almost verbatim notes easily wasn't making me absorb the material at all, so I started spending more time afterward tidying everything up to make things stick a bit better.

> Even more impressive is what the Goodsteins did with the "Lost Lecture" to recreate the figures from just a few pages of surviving notes that looked like this: https://i.imgur.com/zQessy9.png

That's really cool. That note looks about as inscrutable as the ones I have from when I was being taught a crash course in QCD.


Feynman's ability to give an off the cuff lecture is astounding and probably an area where he is world class. I think of the one recorded interview with him, and his shockingly deep answers to simple questions that were off the cuff. His response to "why do magnets push/pull eachother" and what the issue is with asking "why" requires a lot of introspection is stellar.

I linked the "why do magnets do that?" interview elsewhere in the comments, but if anyone else missed it I highly recommend it: https://www.youtube.com/watch?v=Q1lL-hXO27Q


It's hilarious, especially given that I have memories of similar rlogin vulnerabilities -- various unixes being vulnerable to rlogin -l '-froot' in the 90s.

Yah. There's something that feels unjust about it -- the perception that the people cutting are getting something over on you -- that causes us to want to behave badly.

But even if 2 dozen people go around you and creep into that following space, you've been cost like 45 seconds at worst. Better not to play the game.


Also, it really doesn't happen that often. I'm that guy following at 3 or 4 car lengths in rush hour traffic and people aren't constantly funneling in front of me. It's a hypothetical "problem" that is bigger in your head than in reality.

Sometimes I think it's just people's reflexive scarcity mindset that tells them "that spot must not be that desirable or someone would be in it."

Regarding the broader topic of hitting your brakes, I find that I can commute 20 miles in stop and go traffic and only tap my brakes a couple of times. Helps to pace yourself behind the car 3 cars ahead of you instead of the guy right in front of you.


I'm that guy following at 3 or 4 car lengths in heavy traffic an people are constantly funneling in front of me, all to go exactly the same speed they'd be going if they were behind me.

It's arguable that their average speed must be ever so slightly higher than yours if they passed you. ;)

Society would have a lot fewer car accidents if we, collectively, could get over that "Oh no someone dared to get in front of me!" feeling.

We'd also avoid a lot of accidents if we stopped the people that are doing lane changes for position-jockeying and no other purpose.

So it's bad to be mad while driving, but there's a lot of lane changes that deserve the ire. (It's a tiny fraction of drivers that get really bad, but a less tiny fraction of lane changes.)


Being angry at them won't change their behaviour, but will make you more stressed. Remember: driving like that is its own punishment, because they'll be extremely angry and frustrated at everything. Between that and the realisation that driving 2% slower adds about 1 minute more per hour of driving you have to do, I find I can avoid stressing at people lane weaving and have a nicer journey myself.

> Being angry at them won't change their behaviour

Yes, but the comment above was about society collectively making a decision, so that's the context I responded in.

And while it's relaxing to not worry about your own exact speed, I don't see how that lets you avoid stressing about the people that are lane-weaving. They're acting dangerously and I need to be ready to react to them.


Unless they careened into your vehicle while making the lane change, just calmly allow your vehicle to drift away from theirs until you have a safe buffer again, and take joy in the fact that it didn’t meaningfully impact your arrival time, but you’ve meaningfully impacted the safety of your immediate surroundings.

How about you let the police do the enforcement, and focus on your own driving?

I already do nothing about it when driving, so no changes needed there.

And the police don't enforce this.


They are likely getting more frequent brake pad replacements.

Not a significant cost. But they sure as shit aren't getting what they think they're getting. Meaningfully farther ahead.

I now see it all as a risk assessment rather than as ritualistic combat.


If you added a missile launcher to your vehicle, it could become ritualistic combat again.

The question is, -- is it a deliberate democratic outcome, or is it an accidental consequence of local zoning codes and city planning?

If governments are involved in planning, it's legitimate to use laws and the planning process to try and push these processes out of local minima towards more globally optimal outcome.


> If we want our respect for democracy to be taken seriously we need to respect democratic outcomes ... even when they are not the ones we prefer.

>> The question is, -- is it a deliberate democratic outcome, or is it an accidental consequence of local zoning codes and city planning?

>> If governments are involved in planning, it's legitimate to use laws and the planning process to try and push these processes out of local minima towards more globally optimal outcome.

In a democracy, government planning is supposed to push the process towards local preferences. It's not supposed to "push these processes...towards more globally optimal outcome," which when decoded means "what you or what some distant technocrat prefers."


Governments should be working on multi-generational scales. Not "fads" of what people want because they saw it in a movie or they grew up with it.

> Governments should be working on multi-generational scales. Not "fads" of what people want because they saw it in a movie or they grew up with it.

If the people disagree with you, then you're not talking about democracy, you're talking about "benevolent" authoritarianism ("we know what's good for you, and that's what you're going to get, like it or not").

Just be clear what you're really advocating for.


No, what we need is not "democracy" as in "we get what every idiot thinks is good off the top of their head".

What we need is a representative democracy, where our representatives genuinely care about getting the best outcomes, so they enlist experts who actually know what they're talking about, and make policy based on that.

Yes, sometimes that will disagree with what the masses want—and in most of those cases, that means that our representatives need to enlist some communication experts to explain why it's actually best.

Democracy isn't an end in itself. It's supposed to be the means to an end of better governance for all. We don't have to accept things that are actively worse for us just because 50%+1 of the relevant voters think they're better right this second.


Since when is government a democracy? Roman times or something like that? Most? Some? Or at least a few government officials are elected. Pretty sure most are hired.

Since today. We elect our representatives and they are supposed to reflect the people's wishes as they go about their duties. Some city government staff might be hired employees, even most. But they are still fundamentally accountable to the elected representatives, and thus to the people.

They run an election based on a platform. You are voting for the person and the platform. They aren’t there to do your wishes, but to accomplish their agenda the people “agreed” was the best of all options that election cycle.

Sometimes this agenda is altruistic, like reducing crime. Sometimes it is populist, or social, or even fascist. Even then, elected officials are supposed to have limited power, not unlimited power. In some (many, depending on where you live) cases, they’re not even accountable to the people — the people can’t recall them, to remove them is a political act by other parts of government.


When you pan out, walkable neighborhoods are at the multi generational scale — car centric suburbia is the fad.

> In a democracy, government planning is supposed to push the process towards local preferences.

In a representative, constitutional democracy, we're supposed to elect people who can more fully understand issues and possible outcomes, and work from there to create a system of laws and policies that is predictable and fair to all the parties.

This means that not every policy will be fully understood or agreed with by the populace. If we wanted to just implement what the public wants, we could just directly vote on every issue.

Orthogonally, there's a whole lot of the fabric of our daily lives that is just a certain way because that's how it's been so far. It works, but is neither popular nor unpopular-- it just is. That doesn't mean it couldn't be better.


There's also been studies showing how changing infrastructure designs can often be most unpopular just before the change but then become very popular after once the effects of the change are actually felt.

Change-- especially infrastructure change- almost never does anything good immediately and tends to screw everything up, too.

> [2] it becomes rapidly less fine when the company essentially has a monopoly over a system requires to participate in modern life, but that's a different topic...

That's the real thing here. Concentrated power is scary-- whether it's the federal government, Visa/Mastercard, Google, etc.

At least power concentrated under the control of a government might be held accountable to the people. With private, concentrated power: fat chance.


I'm working on making it a thing, but my theory is that power can't be destroyed, merely transferred, and in most cases I'd rather have the power be vested in a democratic government.

Suppose an asteroid strikes the Earth and all human life becomes extinct. What power, specifically, has been transferred, and to where?

When an asteroid strikes Earth, its kinetic power is rapidly transferred primarily to the atmosphere, surface, and subsurface in the forms of thermal energy (heating and vaporization), mechanical energy (crater formation and ejecta), and seismic energy (earthquakes and waves).

If a tree falls and no human hears it did it make a noise?

The best option is it being decentralized and diffuse and operating through market mechanisms.

If that leads to bad outcomes, then government is a next best choice.

(Of course, all the special cases, natural monopoly, etc etc etc-- government has a role in addressing the bad outcomes associated with those).


Big revenue + small margins in a stable business, IMO, is a massive liability for the bottom line; any downturn in business and that becomes big revenue + big losses. Even if cloud is making money, it can wipe a lot of that out.

From the point of view of running an enterprise that lasts, though, diversification is important. Financially diversification is probably, in general, bad for EPS. But if you want to run a lasting empire, it's best to not tie it to just a narrow thing.


That depends on the business. People are not going to stop eating so small margins in the grocery business isn't a negative - the revenue is mostly recurring and recession proof (some people might switch from buying meat to rice+beans, but other people are going to stop eating out and so it balances).

Just because people need a grocery store doesn't mean that you're guaranteed to make money running one.

multiplying huge revenue by a small percentage to get a big positive number

to multiplying huge revenue by a small negative percentage to get a big negative number

So that's how Kroger managed to lose billions over the last couple of quarters, or how small changes in shoplifting/shrinkage based on store makeup can cause losses to some chains, etc.


https://massmarketretailers.com/kroger-delivers-solid-quarte...

They didn't lose money because of their grocery operations. Those margins have increased slightly.


They lost money because of their grocery delivery operations.

Their margins have increased slightly if you ignore the part where their efforts at grocery fulfillment blew up.

Just because an industry is essential doesn't mean that every firm in it makes money.


I agree, all kinds of grocery stores have failed over the years. Kroger's just isn't a good example of a failing store for a lot of reasons. They aren't a stellar investment, but they are also up from 1 year ago and 5 years, so investor's don't look like they agree with your summary of the business.

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