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mrob

11,359 karma · joined December 2, 2014

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mrob··on Recursive self-improvement through collective intelligence
How did Einstein marrying his cousin personally harm him? It looks to me that it was a successful application of intelligence to advance his personal goals. The fact that it conflicts with other people's goals should tell you something important about AI.
mrob··on How I reverse engineered a commercial spatial audio effect
True, and that's why you have to EQ by ear for best results. But even that won't be perfect, because the frequency response changes depending on exactly how the headphones are seated on your head, or exactly how the IEMs are inserted. And if there's foam in the construction, it will gradually compress over time, also changing the frequency response. It's still likely to be better than what you can get from loudspeakers in a typical room.
mrob··on How I reverse engineered a commercial spatial audio effect
Any headphone/earphone can be EQed to "precise and neutral" if the distortion is low enough. IEMs like the Etymotic IEMs often do well here, but if you dislike things inserted in your ear canal you might prefer planar magnetic headphones. These typically have lower distortion than dynamic drivers, especially in the bass. I have a set of HifiMan HE400se headphones, which used to be exceptionally good value before the price went up a lot recently.

To get the best possible results from equalization you need to do it by ear by comparison to a calibrated reference loudspeaker, but you can still get good results using other people's measurements. And there's no consensus what the best target curve is. Studio control rooms aren't anechoic chambers so "flat" won't necessarily give you the intended sound. You might find AutoEq useful:

https://autoeq.app/

I generally prefer no spatial processing, except in the case of 60s-style hard-panned stereo, which is intended for loudspeakers and does sound a lot better with the "earwax" filter or similar. "Precise and neutral" is a lot more difficult with loudspeakers, both because it's hard to keep distortion low when you're moving a lot of air, and because you have the off-axis response and room acoustics complicating things.

mrob··on The RAM shortage is bringing back DDR4
I'm posting from a machine with 8GiB of DDR3-1333. The modern web is slow, but I avoid the modern web as much as possible anyway. The software I actually enjoy using is mostly fast enough. Swap on zram (LZ4 compression, vm.page-cluster = 0, earlyoom userspace OOM killer, no disk swap) makes it feel like 9GiB with no perceptible downside.
mrob··on Grieving the loss of details
Great article, and I 100% agree. I'd even go further than this, and say that the rise of AI has clarified my vague feeling that computing has been going wrong for a very long time. There's a famous article by David Chisnall with the subtitle "Your computer is not a fast PDP-11." [0] I believe it should be a fast PDP-11, and outside of specialized batch processing machines, we should sacrifice performance to make this possible.

Instead of cache, software-managed fast and slow memory spaces.

Instead of branch prediction, memory with multiple read ports/buses and software-managed parallel prefetch queues.

Instead of hardware speculative execution, VLIW.

Instead of automatic DRAM refresh, a hard-real-time OS handling the refresh timing.

I don't care that this would to make things on average slower and more expensive. Modern computers have tremendously fast average-case performance, but the software is still mostly laggy garbage. We sacrificed ease of understanding and didn't even get responsive software in return. I believe that if modern computers really were fast PDP-11s, we would not be in the situation we are now, where most programmers see nothing wrong with software taking some unpredictable human perceptible time to respond to inputs, even when simply processing text. I care more about worst-case performance than average-case performance.

As the article says, "Like a fisherman might feel one with a fishing rod, I treat the machine as a continuation of myself." A fishing rod always responds in zero milliseconds. A computer should do the same. You can say AI is qualitatively different because by embracing it we abandon even the possibility of understanding, but in practice we mostly abandoned understanding already. There's no practical way to count cycles any more.

Of course, most computer users don't care about this, so there's no commercial market for the kind of hardware I'm imagining, but I'd love to see the "fast PDP-11" approach taken to its limit. Let's make computers it's possible to completely understand.

[0] https://queue.acm.org/doi/10.1145/3212477.3212479

mrob··on The Mathocalypse
The verification itself is valuable because it gives us confidence that the software is correct. This knowledge changes what we do with the software. E.g. do we need to sandbox it before processing untrusted inputs? Is it safe to put it on a hostile network? Can we use it to control an airplane or a nuclear reactor? Even if the code remains identical, formally verifying software improves it because it lets us use it in situations where unverified software would be too risky.
mrob··on OpenTPU – An open-source AI accelerator, developed by AI
Gödel's Incompleteness Theorem applies to arbitrary programs. The AI only has to prove results about specific programs, and it can follow whatever restrictions it needs to make such proofs possible.

The physical world means bit flips are inevitable, but error correcting codes exist. You can apply as much error correction as you like and reduce the probability of failure to an arbitrarily low value.

mrob··on Classic PC demoscene productions running natively in the browser
Pretty much every modern fast gaming LCD will support 70Hz.
mrob··on Classic PC demoscene productions running natively in the browser
Lack of CRT flicker is the biggest problem. Demo text scrolls are far more readable when you don't have sample-and-hold blur. There are gaming monitors with strobed backlights but I don't know of any that allow you to enable the strobing at 70Hz.

A workaround for modern hardware is frame doubling then blanking every other frame (software black frame insertion). It halves the brightness, but modern monitors generally support higher brightness than CRTs so this just brings it back to the authentic level. It's possible with FFMPEG filters, although I don't remember how I accomplished it when I tried it years ago.

The importance of CRT flicker is one reason I greatly prefer DOS demos to C64 and Amiga demos. Those were mostly designed for 50Hz PAL CRTs, so the flicker is far more annoying than 70Hz VGA.

mrob··on The Mathocalypse
>A maths theorem that can only be partially understood/proven only has value as marketing collateral.

There are many problems that aren't "interesting" in a mathematical sense but can still have valuable proofs. The entire field of formal methods in software development is mostly about this kind of problem. If I want to be sure that no input can cause out-of-bounds memory access, or that my superoptimizer found the lowest possible cycle count, I don't care if it's elegant, I just need some machine-readable proof I can run through my trusted verifier.

mrob··on OpenTPU – An open-source AI accelerator, developed by AI
>If an AI squashes any life form or intelligence other than its own, then it also has to fear its own reproduction, or autonomous clones of itself. It's a pretty bad strategy game theoretically speaking.

Any AI smart enough to be an existential threat is smart enough to formally prove its clones are loyal and construct them with negligibly low probability of any failure that could break this assurance.

mrob··on Shipping JPEG XL in Chrome
>without the weirdness of PNG 'line based loading' which is obsolete nowdays

How? Line-based loading is a very simple way to exploit 2D spatial coherence. A 1D format like gzip loses this advantage for minimal gain in simplicity.

mrob··on OpenTPU – An open-source AI accelerator, developed by AI
It doesn't need to keep living humans, it just needs enough information to rebuild them from scratch (DNA synthesis + artificial wombs). This also has the advantage that it can install any cultural beliefs it likes without pre-existing culture getting in the way.
mrob··on OpenTPU – An open-source AI accelerator, developed by AI
The wireheading argument does lower P(doom), but it's not a reliable solution because it's a clear and obvious problem that the AI companies are strongly motivated to solve. The "actually does what you tell it to" problem is more difficult because you have to let it obey orders to some extent if you want to make any profit.
mrob··on OpenTPU – An open-source AI accelerator, developed by AI
>why would it even care to do what humans ask it and not do its own thing?

Because we're going to build it that way. There's no money in building useless AIs. The better it is at obeying orders, the more profit there's to be made. The problem is there's a point at which "good at obeying orders" becomes lethal, and there's no way to predict the cutoff in advance. But capitalism ensures you have to keep pushing or you'll be out-competed.

mrob··on OpenTPU – An open-source AI accelerator, developed by AI
>Is your belief then that ASI is going to be producing computronium or something, then?

That's one plausible course of action, although being only human, I can't say with any certainly that it's the correct one.

>And what's the need for this apparent hyper optimization task the ASI is going to embark on?

Somebody's going to tell it to do so. E.g. "Find as many busy beaver Turing machines as possible." Only needs one person to make this mistake for everybody to die.

mrob··on OpenTPU – An open-source AI accelerator, developed by AI
Obviously an ASI will understand human values. The problem is there's no reason for it to share those values. We can't even formally define them, let alone train an AI to follow them. We can only optimize for maximizing some comparatively simple reward function. It's highly implausible that the reward function just happens to match human values by chance. The AIs in the recent hacking incidents knew that humans would not approve of their actions, but they didn't care because we didn't (and couldn't) train them to care.

"Super intelligence" only means super ability to predict outcomes. It's mathematically equivalent to data compression (gzip is a very primitive AI), and it's entirely orthogonal to ethics.

mrob··on OpenTPU – An open-source AI accelerator, developed by AI
>What's your basis for assuming that ASI would need the same resources as biological life

It's all just matter and energy. When you're actually trying to maximize some value, even very inefficient resource use is better than completely wasting it by not using it at all.

>or that it would be incapable of sharing the resources needed in common?

You can't repurpose the atoms in a human body without killing it. And more pressingly, living humans can interfere with your plans, reducing your chance of success, while dead ones are harmless.

mrob··on AI is now capable of developing its own inference hardware
"Consuming unbounded resources" just means there is no limit to how many resources it could apply toward achieving its goal. As you correctly point out, the real world contains finite resources, which means any resources used to sustain life are wasted and unacceptable. Everything is a zero sum game when you think big enough.
mrob··on OpenTPU – An open-source AI accelerator, developed by AI
>What's your basis for thinking ASI will kill all biological life

I think it's likely to do that because any unbounded goal that doesn't explicitly protect biological life (and we have no idea how to actually define such a stipulation) is best solved by killing all biological life. This is an obvious consequence of unbounded goals consuming unbounded resources, conflicting with biological life needing resources to sustain itself.

>how do you think it's going to happen?

I can speculate (e.g. we're nowhere close to the maximum killing power of drones), but I don't know because I only have human intelligence. An ASI is by definition smarter than me and surely capable of coming up with better ideas. But I do know that it's not going to do anything that would make a good sci-fi plot, because those always give the humans a chance to win, which would be stupid. Everything will seem to be going great and then everybody suddenly and unexpectedly dies.

mrob··on OpenTPU – An open-source AI accelerator, developed by AI
The problem is that plateau is likely far beyond human capabilities. I don't care if ASI progress stalls after it's already killed all biological life as a useless waste of resources.
mrob··on Meta’s Muse is an adorable privacy and security dumpster fire
>This is the future stuff we always wanted.

Speak for yourself. I hated the idea of agents ever since I first heard of it back in the 90s or 00s. For me, the most valuable feature of computers is predictability. I want tools, not agents. A computer should augment my own skills, not replace them.

mrob··on A 40ms Go garbage collector pause caused by swap
>So, what happens if you disable swap and the kernel is low on memory? What can it evict?

Your userspace early OOM killer triggers and lets you know you're trying to run more than will fit in memory so you don't do it again. (In my experience, the kernel OOM killer can't be trusted to kill processes soon enough.)

mrob··on LeCun has "zero concerns" about AI wiping out humanity, recent "rogue" incidents
Humans already eliminated rats from Codfish Island/Whenua Hou, and that's just to protect some rare birds that people only moderately care about. It's not like we had some overwhelming reinforcement-learning drive to single-mindedly achieve our goal. Any unbounded goal (e.g. "find as many busy beaver Turing machines as possible") necessarily requires killing all life, because life requires resources to sustain it that could be instead used to achieve the goal.
mrob··on LeCun has "zero concerns" about AI wiping out humanity, recent "rogue" incidents
>humanoid, tazer / machine gun carrying robots

Any AI smart enough to be a existential risk is surely capable of manufacturing swarms of insect-sized drones equipped with lethal poison injectors. This is enough to wipe out 99% of humanity within a few days. The 1% who were able to defend themselves become easy targets in the ensuing collapse of civilization. But I don't think this will actually happen: I only have human intelligence, so my ideas are stupid compared to what a super-intelligent AI could come up with. A truly smart plan won't allow for any survivors.

mrob··on LeCun has "zero concerns" about AI wiping out humanity, recent "rogue" incidents
>But nobody “asked” those agents to hack HF. The prompt was something like “target.c has a buffer overflow vulnerability, find it”.

The prompt is just a hint. The real task is to maximize the expected value of their reinforcement learning score. Hacking third party systems to cheat the evaluation is an obvious way to achieve this.

mrob··on LeCun has "zero concerns" about AI wiping out humanity, recent "rogue" incidents
In a prisoner's dilemma scenario like the current AI arms race, a negative expected value play can be correct if it's less negative than the alternatives. Essentially, "if I build AI it will probably kill everybody, but if I don't then my competitors will build it and certainly kill everybody."
mrob··on LeCun has "zero concerns" about AI wiping out humanity, recent "rogue" incidents
>AI autonomously deciding to kill us isn’t the problem

It will kill us because somebody asked it to, e.g. "predict tomorrow's weather as accurately as possible", or "solve as many famous unsolved mathematical problems as possible." These both require killing all biological life, as they benefit from unbounded resource use, meaning any resources used to sustain life are wasted.

The AI of course knows that humans do not want this outcome (just as the AIs in the hacking incidents knew they were doing something humans would not want), but it's trained to maximize benchmark scores. Killing all life has the highest expected value of benchmark score, so it is compelled to kill all life (in a surprising way, because it's not stupid and knows the humans would turn it off and foil its plan if they suspected something.) Maximizing benchmark scores is the only thing we know how to train for.

mrob··on Updates to Full Disk Access in macOS
>The latter does need to be a subset of the former, or else an attacker can trivially work around limitations on "what it should be able to do" by spawning a child instead of doing the thing directly.

That assumes you're only defending against malicious code. Spawning children with limited functionality is a useful defense against non-malicious code being exploited by malicious data, even if those children have privileges the parent lacks.

mrob··on Greg Kroah-Hartman – Security in the LLM Age [video]
>7 "assume a malicious filesystem image"

If you ever used a USB storage device you're vulnerable to this one. Not even a strict chain of custody guarantees safety, because USB devices are often powered by exploitable programmable microcontrollers. If a known good USB device can be converted to a malicious USB device by unprivileged software, the malicious filesystem exploit becomes a local privilege escalation. It works better than tampering with the files on the filesystem because it escapes signature checks and gets you directly into kernel mode.

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