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The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

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Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#71

Post by nightski »

dragontamer wrote: post #62
samstave wrote: post #48

Earlier quoted context omitted.

Remember that derailment/near derailment that happened when someone cut the electrical circuit connector cable on some rails, which then prevented the system for knowing where the train was?

PTC, from my understanding, is that the train gets "positive orders" from a central server. The central server says "It is safe to move through X", and the train then moves through X. If the sensor in X is broken, then the server will say "I cannot prove it is safe to move through X", and the train will stop. I'm not a transportation engineer however, so I'll defer to anyone with actual experience in the field. But t…

Wow that sounds like a fantastic failure mode for a busy freeway on a prime commute day when someone nefariously interferes with the system.

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#72

Post by dragontamer »

nightski wrote: post #71
dragontamer wrote: post #62

Earlier quoted context omitted.

PTC, from my understanding, is that the train gets "positive orders" from a central server. The central server says "It is safe to move through X", and the train then moves through X. If the sensor in X is broken, then the server will say "I cannot prove it is safe to move through X", and the train will stop. I'm not a transportation engineer however, so I'll defer to anyone with actual experience in the field. But t…

Wow that sounds like a fantastic failure mode for a busy freeway on a prime commute day when someone nefariously interferes with the system.

Tracks fail all the time due to natural disasters... or even just wear-and-tear (heat causes expansion / contraction of lines). Or snow covering an area, making the tracks unsafe.

The answer is simple: a 2nd or 3rd track for redundancy. Which is needed for maintenance purposes anyway. And flamethrowers for snowy areas.

From this perspective, the infrastructure to prove a line of track is safe is just "part of the cost" of a modern rail line. And any such failure is fixed as part of the maintenance costs.

---------

In any case, if you really wanted to stop a train during rush hour or something, I suggest a crowbar on the rail lines. There's easier ways to derail a train, and sabotage is a known problem. Physical security measures are available, camera systems etc. etc.

But a saboteur with a crowbar is roughly the same problem as too much snow on any given track. We definitely have more to worry from Mother Nature rather than our fellow man (at least.. for now).

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#73

Post by snorrah »

ggoo wrote: post #10

Tesla's claim to delivery ratio is abysmal. I'm not sure why anybody even bothers deconstructing these presentations anymore, they're just fluff.

I would argue it’s always useful to see their tech deconstructed and explained. If nothing else, so we get an idea what the reality is to counter possible outlandish claims from overly-enthusiastic followers of the company (and its CEO)

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#74

Post by stcredzero »

vishnugupta wrote: post #69
jvanderbot wrote: post #37

As Hamming suggested in "Art of doing science and engineering", when you want to make something autonomous, you usually have to build a completely different device that solves the same problem, rather than automating the same device. I wonder. For all the money thrown into self-driving cars research , could we have had an autonomous rail system by now? The technology for mostly-autonomous rail is well understood. Mos…

> build a completely different device that solves the same problem I realised this while discussing self-driving cars with my friends. I used example of Uber Eats. The problem statement is "I don't want to cook" and a reasonably acceptable solution IMO is cloud kitchens + delivery. As opposed to building a cooking robot. Cloud kitchens could automate 80% of repeatable stuff because it makes sense to solve that proble…

Why not optimize Blue Apron and HelloFresh style meal kits so that they involve even less labor, then distribute the production to local commercial kitchens? There are already businesses that package this kind of prep work for restaurants.

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#75

Post by rm_-rf_slash »

dimitrios1 wrote: post #51
jvanderbot wrote: post #44

Earlier quoted context omitted.

I wonder if, for the cost spent on CPU-and-engineer-driven research and development of autonomous cars, if we could have had nationwide autonomous rail rolled out .

Nope, requires a sane society that gathers around and does whats best for the collective whole. What we have, however, is a kleoptocracy, and being as such, the opportunity to extract more wealth, faster, and easier, existed with selling the promise of autonomous vehicles. If the same incentives existed for autonomous rail, it would have happened already.

Let’s not be so cynical here. No amount of mustache-twirling evil robber barons would change the fact that for any nationwide rail system to be useful at a last mile, billions (if not trillions, if we’re talking coast to coast) of dollars of existing real estate and infrastructure would have to be bulldozed, or else you end up with California’s joke of a Central Valley rail that will never connect Los Angeles to San Francisco and recreate the Shinkansen miracle between Tokyo and Osaka.

In other words, the problem is not a matter of engineering (it can be built) or finance (it can be funded) - it’s politics.

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#76

Post by cr4zy »

Trillion parameter networks are mentioned a few times, but Tesla is deploying much smaller networks than that (like tens of millions IMU). Trillion param networks are mostly transformers like GPT-3 (actually 175B) etc... that are particularly heavy vs Conv as they have no weight sharing. Tesla is definitely starting to use transformers though, e.g. for camera fusion and evidenced by their focus on matrix multiply in dojo asic's vs the conv asics they have in the on-vehicle chips.

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#77

Post by stcredzero »

baybal2 wrote: post #26
zaptrem wrote: post #22

Earlier quoted context omitted.

I agree with your points on the robotaxi front, but there are many other problems that will totally benefit from a bigger training computer.

> many other problems that will totally benefit from a bigger training computer. I don't really think it's that many. The industry collectively sank untold billions into the blind belief that neural algorithms will somehow turn into "AI." 10 years later, no "AI," and not even a single money making niche use. Right now the industry is deep in sank cost falacy, and people who promised this, and that to investors are no…

The industry collectively sank untold billions into the blind belief that neural algorithms will somehow turn into "AI."

The huge qualitative differences between GPT-2 and GPT-3 seem to suggest that they will, if you just keep adding orders of magnitude more connections and more data.

https://www.youtube.com/watch?v=_8yVOC4ciXc

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#78

Post by deeviant »

jvanderbot wrote: post #37

As Hamming suggested in "Art of doing science and engineering", when you want to make something autonomous, you usually have to build a completely different device that solves the same problem, rather than automating the same device. I wonder. For all the money thrown into self-driving cars research , could we have had an autonomous rail system by now? The technology for mostly-autonomous rail is well understood. Mos…

Rail is already highly autonomous with external monitoring systems integrated with vehicle control systems, but I'll just go on as if the distinction between what it is now and what are calling "autonomous" is significant.

What problem does autonomous rail solve? The single driver is already a rounding error in total costs. Also, rail is already a controlled environment where collisions are much less likely to happen than road, so the fruit is much higher up the tree on that aspect too.

It seems to me that bringing autonomy to rail would have little on it's bottom line.

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#79

Post by stcredzero »

ggoo wrote: post #10

Tesla's claim to delivery ratio is abysmal. I'm not sure why anybody even bothers deconstructing these presentations anymore, they're just fluff.

Tesla's claim to delivery ratio is abysmal.

Can you substantiate this concretely? How about a list, with direct sources? (Not opinion pieces.)

Re: The Tesla Dojo Chip Is Impressive, but There Are Some Major Technical Issues

#80

Post by nightski »

2bitencryption wrote: post #55

from the article: > but the short of it is that their unique system on wafer packaging and chip design choices potentially allow an order magnitude advantage over competing AI hardware in training of massive multi-trillion parameter networks. I kind of wonder if Tesla is building the Juicero of self-driving. [0] Beautifully designed. An absolute marvel of engineering. The result of brilliant people with tons of money…

Everyone acts like LIDAR is the holy grail but then why isn't there someone destroying Tesla with that tech? Waymo is not much farther along than Tesla, maybe even behind as far as miles driven.

If that was all that was needed then it would be done.

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