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fpgamlirfanboy

Re:More on x86 – The Chip Letter on Thursday April 25, 2024 @11:44AM (#40158917)
i don't have an outrageous amount of experience here but i work at a place that designs and sells x86 chips (and i work on arch adjacent things). i'll just say this: do not underestimate the effect of institutional friction/momentum/complacency on "time to ship". point being: maybe RISC is more "agile" than CISC but also maybe Tenstorrent could have chosen a CISC approach and still iterated quickly simply because they're not an institution.

edit:

> They are working on 2-3 CPU designs, 2-3 AI accelerators, all the IO stuff, etc

also do we actually know how much they're designing wholecloth and not buying off the shelf?

edit2: i think Tenstorrent is great and i'll probably buy a devkit soon (as well as maybe apply lol...)

Re:Intel Meteor Lake's NPU on Tuesday April 23, 2024 @11:36PM (#40140248)
this is very common. lots of companies around (e.g. cadence) that sell SIPs as synthesizable RTL for easy integration into chip designs (and lots of hardware companies buy these SIPs).
Re:Intel Meteor Lake's NPU on Tuesday April 23, 2024 @11:25PM (#40140180)
1024 fp16 macs is pretty good but the 128b vector datapath is weak sauce. on the other hand 2MB SRAM is legit. i wonder how many tiles (i don't think it's in the post).
Re: on Friday April 19, 2024 @10:00AM (#40086928)
https://en.wikipedia.org/wiki/Brown_%26_Williamson#Controver...

> Wigand turned his attention to improving tobacco additives, some of which were designed for "impact boosting", using chemicals like ammonia to enhance absorption of nicotine in the lungs and affect the brain and central nervous system faster. Wigand believed this process was a deliberate attempt to increase addiction to cigarettes.

Re:Women Who Code Closing on Friday April 19, 2024 @09:57AM (#40086902)
> It's easy to assume you're great especially working under "passion coders" who keep stuff afloat.

i work on compilers+hardware so that's the backdrop here.

here's a real hypothetical for you (ie it happened but i'm not going to use specifics): our internal proprietary compiler is spitting out incorrect atomics instructions that deadlock our internal proprietary multi-core DNN accelerator. this incorrect code is downstream of a big, lucrative, customer's (you know which one) LLM model.

now the question: is it the "passion coder" that will solve this or the grinder?

Re:Women Who Code Closing on Thursday April 18, 2024 @10:03PM (#40082772)
> well because they have other priorities and responsibilities in life that make it necessary to maintain a strong work ethic.

It's amazing how many people in tech can't imagine that the same people that can grind med school or IB or big4 accounting or white-shoe law somehow can't grind the same way in tech. Newsflash: the majority of people in FAANG are grinders not "passion coders".

Personally I hate this job but I'm very good at it and it was either law school with my 98% LSAT or tech. I picked tech because reading and writing briefs all day seemed somehow worse.

Re:The Rust Calling Convention We Deserve on Thursday April 18, 2024 @09:50PM (#40082714)
> Side-note: Mojo has been designed by the creator of LLVM and MLIR to prioritize and optimize vector hardware use, as a language that is similar to Python (and somewhat syntax compatible).

Are people getting paid to repeat this ad nauseum?

Re:AMD unveils Ryzen Pro 8000-series processors on Tuesday April 16, 2024 @02:51PM (#40055788)
> the same AIE-ML coprocessors

they're not the same - versal acaps (whatever you want to call them) have AIE1 arch while phoenix has AIE2 arch. there are significant differences between the two arches (local memory, bfloat16, etc.)

Tell that to PhD advisor that took credit for all my work because they were his ideas (at least so he claimed).
Re:Open source versus Microsoft: The new rebellion begins on Monday April 15, 2024 @10:28AM (#40040984)
you see this kind of wishful (delusional?) thinking very frequently on hn:

> Microsoft won't ever be able ... their business model is ... have had enough.

statements made with complete certitude, as if these things aren't nebulous to begin with or in the process of being decided. it reads like the opening line to a christopher nolan superhero movie (i.e., a call to arms) rather than a position or even an opinion.

i personally don't understand what people get from the act of writing/posting such things - i mean i'd get it if we were on some hill about to rush into battle but this is an anonymous/faceless tech news forum.

It's funny - former Google devs (whom I just maintain a good relationship with their former employer) are ideally positioned to profitably take advantage of the arb of TPU over GPU.
With all do respect, I think you're telling a half-truth here. Your LinkedIn profile shows you had two MS degrees before starting your PhD. Undoubtedly you got some of the requirements waived for the PhD course requirements. That means your total time post BS was 5 years. I did the same thing - 1.5 years (3 semesters) MS and then came back later (different school) to do a PhD and got half the course requirements waived. Finished the PhD in 4 years but total time post BS was a more humble 5.5.
Re:Intel Gaudi 3 AI Accelerator on Wednesday April 10, 2024 @10:12AM (#39990952)
> Vivado is intimidating (as opposed to Yosys/nextpnr which you seem to hate)

i never said i hated yosys/nextpnr? i said somewhere that yosys makes the uber strange decision to use C++ as effectively a scripting language ie gluing and scheduling "passes" together - like they seemed to make the firm decision to diverge from tcl but diverged into absurd territory. i wish yosys were great because it's open source and then i could solve my own problems as they occurred. but it's not great and i doubt it ever will be because building logic synthesis, techmapping, timing analysis, place and route, etc. is just too many extremely hard problems for OSS.

all the vendor tools suck. it's just a fact that both big fpga manufacturers have completely shit software devs working on those tools. the only tools that i've heard are decent are the very expensive suites from cadence/siemenns/synopsis but i have yet to be in a place that has licenses (neither school nor day job - at least not in my team). and mind you, you will still need to feed the RTL or netlist or whatever that those tools generate into vivado (so you're still fucked).

so i don't have advice for you on RTL - i moved one level up (ISA, compilers, etc.) primarily because i could not effectively learn by myself i.e., without going to "apprentice" under someone that just has enough experience to navigate around the potholes (because fundamentally if that's what it takes to learn then you're basically working on ineluctably entrenched tech).

Re:Intel Gaudi 3 AI Accelerator on Tuesday April 09, 2024 @10:10PM (#39986292)
it's so true it hurts
Re:The Elements of Differentiable Programming on Friday March 22, 2024 @11:05PM (#39797087)
hey look someone that actually knows what they're talking about!
Re:The Elements of Differentiable Programming on Friday March 22, 2024 @10:55PM (#39797038)
i haven't a clue what that means but when julia's autodiff is the only one that is implemented using dual numbers i think the claim is pretty obviously false and seemingly everyone has an issue admitting that. without a doubt you'll just say something else sarcastic rather than admit it.
Re:The Elements of Differentiable Programming on Friday March 22, 2024 @10:42PM (#39796978)
is this like some kind of version of truman show? the full sentence is

>please show me the source line number in pytorch or tensorflow that defines this number

why? because the original comment makes a claim about pytorch. it's all right there in black and white.

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @10:15PM (#39796881)
it's amazing to me that pointing out a straight up mathematically factual inaccuracy is considered "angry" and "acting a fool".
Re:The Elements of Differentiable Programming on Friday March 22, 2024 @08:29PM (#39796254)
> I don't know why you keep calling it "magic".

because they have all of the gee-whiz factor of a freshman calc proof of the chain rule that divides and multiplies infinitesmals and absolutely not enough of the substance necessary to prove much more than that. they are absolutely, in the research literature, at best an anachronism (harkening back to leibniz) and at worst a parlor trick.

in literally my first response i provided the most trivial counter-example to the magic of non-standard analysis. no answers (crickets). i surmise this is because the people in here talking it up aren't really serious.

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @07:59PM (#39796098)
i didn't say it cannot be, i said there's a natural reason it's not: the same reason the rest of analysis isn't.

> You're right on one count: no library implements forward mode

there are plenty of CFD type libraries that implement forward mode. they also do not use what i'm calling "magical" dual numbers i.e. these nilpotent ring elements.

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @07:28PM (#39795928)
> It seems like you haven't really worked through this stuff too much

yup not at all - i just wandered in off the street and knew accidentally that you were talking about non-standard analysis.

> The rest of your points I think I have already addressed

please show me the source line number in pytorch or tensorflow that defines this number

> we add one called "h" with h² = 0!

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @07:14PM (#39795829)
> and if addition and multiplication work the way you expect and propagate derivatives correctly - then you are using dual numbers

you literally started out your miraculous comment with

> This new algebra is called the ring of "dual numbers." The difference is that instead of adding a new element "i" with i² = -1, we add one called "h" with h² = 0!

not some observation about caching derivatives.

so i'll repeat myself for the 3rd time: there are no magical numbers anywhere in pytorch or tensorflow or cafe or any other serious autodiff implementation that abide by the rules you so jubilantly exclaim about.

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @07:13PM (#39795825)
> If I (an expert in the field but not the subfield)

someone quoted from their intro - they claim this is for grad students.

again, i'm on point and right no matter how much hn plays devil's advocate for things it (hn) has a fetish (overly mathematical treatments of tech).

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @07:05PM (#39795770)
you guys are wrong and spreading blatant misinformation - there is no magic number whose square is 0 but which is itself not zero anywhere in pytorch or tensorflow or any other real DNN framework that i'm familiar with. it's all fun and games to participate in math woo but you shouldn't be proclaiming things you don't actually know on a public forum.
Re:The Elements of Differentiable Programming on Friday March 22, 2024 @06:59PM (#39795736)
> Most autodiff packages (such as Pytorch) use something not much more advanced than this

pytorch absolutely does not use the dual number formulation - there are absolutely no magic epsilons anywhere in pytorch's (or tensorflow's) code base. what you're calling duals are the adjoints where are indeed stored/cached on every node in pytorch graphs.

there's a reason no one uses dual numbers (non-standard analysis) for anything (neither autodiff nor calculus itself): because manipulating infinitesmals like this is fraught formal manipulation (it's algebra...) where as limits are much more rigorous (bounds, inequalities, convergence, etc.). my favorite question to ask the non-standard analysis n00bs is: please tell me under what conditions this is true

(dx/dy)(dy/dz)(dz/dx) = 1

edit:

anyone that thinks i'm wrong and this other guy is right should go and do some reading, eg where this guy tried to make this same point and got shot down:

https://math.stackexchange.com/a/341550

spoiler alert: there's a reason you had to learn epsilon-delta proofs and limits and it's not because your math professors are mean.

this is why i hate this kind of "TIL, gee whiz" math tidbits - they're full of exclamation marks and fancy sounding words ("non-archimedean rings" oooo fancy) but almost always come from a wikipedia level understanding, not actual research.

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @06:30PM (#39795534)
> I mean, yes…? Maybe I’m a terrible programmer but I’ve never applied calculus to my work in any real way. A book that’s just “calculus applications for software design” seems quite useful, and quite unrelated to teaching “math” in a direct way.

that's not what this book is. like i said in the first sentence right there in the part right before the all caps calculus - this is book is a compendium of theorem/proofs/etc. very little actual software.

> Doesn’t this apply to all books of any kind?

again, i already covered this: a pedadogically sound textbook will have exercises and structure/themes/etc rather than just 120 "propositions".

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @05:09PM (#39794898)
> graduate-level introduction to differentiable programming.

go check out any real graduate textbook. what you will find is they all have exercises.

> It's a book for ML researchers. I'm excited to read it. Calm down.

just because the authors claim something doesn't make it true. i'm not wrong - this is not a good pedagogical resource and i would bet a year of my salary (as an ML researcher) that you will in fact not read more than 5% of this book.

Re:The Elements of Differentiable Programming on Friday March 22, 2024 @04:09PM (#39794312)
i don't know why people write these things. it's an absolute hodge-podge of theorem/proofs/results/techniques with no unifying theme other than "CALCULUS". so it's a pretty bad math book to actually learn math from (you can always spot a pedagogically unsound math book by its lack of exercises). the book doesn't even have any code in it which is surprising considering it has "programming" in the title.

actually i know why people write these but i still don't know why they publish them: this is a phase everyone goes through in their "math" life where they look back on everything they've learned hastily between undergrad/phd/postdoc (or whatever) and they have the urge to formalize/crystallize. everyone has the urge - i had a late-career QFT prof tell me that he was excited to take his sabbatical so that he could finally do all of the exercises in peskin&schroeder for real real and type it all up neatly.

i've done it too, in-the-small (some very nice notes that i'm proud of, on various things). you sit down, make your list of things, pull up all of the books/papers you're going to use as references and you start essentially transcribing - but you tell yourself you're putting your own spin on it (adding ample "motivation"). and it's all fine and healthy and gratifying for you and yourself alone. but i don't think i'd ever imagine to myself "well hmm my organization of these topics is going to be useful for other people i should put it out there for the world to see". but that's just me.

ninja edit:

before someone jumps down my throat about "what's the harm?". the harm is n00b/undergrads/young people/etc will look at this and think this is the right way to learn this material and some of them will even make an attempt to learn the material from this thing and they'll struggle and fail and be discouraged - i speak from experience! it's not a good thing for the community. sure maybe 1 in a 100 can learn this stuff from just reading a monograph (what these things used to be called...) but that's the exception that proves the rule.

Re:Unconventional Uses of FPGAs on Tuesday March 19, 2024 @06:18PM (#39760891)
> This is a personal project aiming to replicate analog coupling dynamics with asynchronous digital circuits FPGAs, not a claim that we can solve NP complete problems with a fundamental speedup.

Then you shouldn't have led with that? It's like academic clickbait to say "here's this thing I'm working on, it uses XYZ technique to solve REALLY HARD PROBLEM" but omit the "...very poorly" part. Like I said I don't entirely blame you, I blame the academics that have an entire cottage industry and culture around these kinds of "results".

> These sorts of Ising architectures get their speed-up are based on oscillator interaction, not parallelism.

Not sure what you're trying to say - it's quantum annealing "brought to life" using simple 2-state (up/down) particles/phonos/whatever you want to call them. The quantum in quantum annealing means superposition ie parallelism; your implementation is basically a D-Wave machine without the qubits.

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