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I think he's kind of speaking past the original author. The original piece is basically about how the author doesn't think that RISC-V will take off outside embedded, because of some design decisions that lead to poor performance compared to ARM64 and because so much of the ISA being optional means that there's too much fragmentation to make binary distribution feasible. Meanwhile, this piece is mainly about how RISC-V is great for embedded because companies can build it into custom chips with specifically the functionality they need, and because of how cheap it is for low-end use cases since there's no license fees.
The only real point of contention I see between the two is that this piece goes on to talk about how it's a selling point that RISC-V can be used for both low-end 10 cent microcontrollers, and high-end multi-core processors running Linux. Personally I don't see the benefit of this since you're going to have to recompile your software anyway, and since all the RISC-V SBCs I'm aware of have significantly worse performance and efficiency than comparably priced ARM SBCs.
The two authors also have a very different definition of what "high-end" means.
Dmitry is talking about high-end application processors that you might find in a mid-range or better laptop, smartphone or server. Armstrong Subero seems to think that anything larger than a "dirt cheap microcontroller" is high-end.
People shouldn't take this the wrong way, but the VexRISC-V cores in Baochip are not "high-end". They are basically as low-end as you can get while still meeting the modern definition of "application core". And that doesn't matter, because being high-end application SoC is not Baochip's design criteria. These cores are actually pretty decent for Baochip's criteria.
The VexRISC-V are implementing the exact style of "classic-RISC" microarchitecture that RISC-V is optimised for. It's basically the optimal niche for RISC-V, before any of the problems start showing up.
I don't think I've ever seen anyone express the opinion that RISC-V can't easily cover the "dirt cheap microcontroller" to "low-end application processor" range, even stretching up into "mid-range application processor". Just that it's really fighting an uphill battle if it ever wants to compete with high-end application processors (and that it's going to struggle in the low-range/mid-range application market because of that).
The huge number of companies building RISC-V chips and really crazy optimizations that they are doing in all kinds of spaces are a very real counterweight to your notion.
And RISC-V is just starting here with shoestring design and fab budget. Wait till all engineering teams really adopt it like Tenstorrent and NextSilicon and so on.
> Personally I don't see the benefit of this since you're going to have to recompile your software anyway
The benefit is a unified toolchain. Make a chip, get the entire software toolchain for free.
In the past if you made your own chip you had to write your own assembler, compiler, debugger, etc. Many manufacturers forked gcc but of course it's still a lot of work and the license isn't great (for them, not the user).
This universal compiler toolchain is massive benefit for both the chip makers and the end user.
Different RISC-V dialects might as well be as different from each other as English is from German. Sure, the cognates, family the resemblance, and common(-ish) alphabet make some things easier, but if you're shipping a manual, you still need to do it both in English and auf Deutsch unless you rely on machine translation.
So it is with the family of mutually incomprehensible ISAs called RISC-V.
I don't really understand the author's conclusions about cost and shipping, and how RISC-V is cheaper and more accessible to people outside the US and Europe. He first talks about how getting $1 worth of chips can cost $60-$200 in shipping for him due to his location... but then by the end claims that RISC-V gives him "an architecture that arrives in my country at ten cents a part".
I don't get how both things can be true. The cost to ship something to Trinidad and Tobago has nothing to do with whether it's ARM or RISC-V; shipping the same weight of either kind of chips should cost exactly the same amount. Yes, maybe the chip cost itself of a particular ARM-based model is $0.15 while the equivalent RISC-V chip costs $0.10, but if the issue (for him and other people who live outside US/Europe) is that shipping costs are orders of magnitude more expensive than the thing being shipped, that chip-cost difference becomes irrelevant.
I think he does make a great point about how fragmentation does give you better optionality: ARM is sort of like cable TV where you have a small number of product categories that each bundle a particular set of features, whereas with RISC-V you design something bespoke that does exactly what you need and nothing more. But again, this isn't going to affect shipping costs.
He's saying that shipping from the big western parts suppliers (Digikey, Mouser, Segger) costs a lot of money. When ordering from AliExpress or Crowd Supply he just gets the cheap postal rates which from China are free. It is very likely a good chunk of the overhead from western part suppliers has to do with export controls and risk aversion.
Aliexpress doesn't do any ID verification hassle. This is all an argument more about distribution and shipping. RISK-V is going to win because getting the parts is insanely cheap and without overhead.
The "fix" is probably Digikey, Mouser, and Segger need to just let buyers check a box where they assume all liability and parts are just thrown in the mail and forgot about - something aliexpress is great at doing.
In addition to what you wrote... what does China use? One could argue that the factories there have very low cost of shipping + economies of scale - they order thousands of units, if not tens of thousands.
Then probably RISC-V being "open" license is the key to its success, even if the architecture itself is weird.
He says:
> From that position, the difference between a ten cent part and a one dollar part is not a rounding error and it is not a detail you get to wave past on the way to the interesting discussion about encodings
Yet earlier:
> I pay anywhere from US $60 to US $200 to ship one dollar chips that people everywhere else get free shipping on
Seems to me that the difference between a 10c chip and a $1 chip are a rounding error when the shipping cost dominates so much?
He explains the difference here:
> I can pick up H417s on the official WCH store on Aliexpress with free shipping and no verification hullabalu.
I think the point is that anyone can make these chips, so there are Chinese sellers who just throw them in a padded envelope and send them out without bothering with all the stuff "serious" vendors do. And because they're cheap enough, if doesn't matter if some get lost in the mail.
I’d really like an explanation here if the author is reading. And how does shipping cost scale with quantity? Can you get that to be small per unit on big orders?
I love the article, it's a breath of fresh air compared to the usual bay area centric takes. However there's just one issue:
> The students I want to teach are in the same position, and so are the ones in Nigeria and Bangladesh
It does not take $60 to ship small sub $1 chips from Asia to Nigeria/Bangladesh. These two countries are all on global trade routes (both supply and demand) and the expensive last mile delivery costs are fairly low there too.
This is a bay area centric take on a non bay area centric take.
The typical bay area centric take has the following vibe:
1. I am among the group of most open minded people
2. I admit mistakes, but I don't change my view, that means I may make the same mistakes next time on a different concrete cases
3. Morally I am among the least corrupted
4. I work for the moderately morally questionable firms with nice paychecks, but my moral views are not tainted a bit
5. I never think on the other's perspectives
Is this comment on shipping costs from Asia to Nigeria/Bangladesh based on your experience? If there is a less expensive way then share the approach to help others :)
It could be bureocratic barriers. For example, Turkey recently changed importing laws so that anything(even stuff sent to you for free) from outside the country is subject to tariffs & import costs. Importing a cheap component worth 1$ costs like 300$.
i don't know how trustworthy rateships.com is, but according to them shipping costs to nigeria and trinidad are similar. and as for the last mile, the cost probably goes up because local shipping is rather unsafe (higher rate of theft of packages).
> from Asia to Nigeria/Bangladesh.
Bangladesh is a country in Asia...
> It does not take $60 to ship small sub $1 chips from Asia to Nigeria/Bangladesh
So don't even try to find how expensive is bring these to Brazil. Even the $5 orders from JLCPCB become infeasible for hobbyists here due to all the roadblocks.
> it's a breath of fresh air compared to the usual bay area centric takes...
HN hasn't been Bay Area centric in years. Honestly, most comments and usership on the platform seems to now align with SWE culture in DACH and CEE.
Presumed RISC-V hate is a perfect example of that - the UCs and CSUs have been using RISC-V in their curriculum since the 2010s becuase Patterson is faculty at Cal and most CompArch courses in both systems have been using RISC-V as a result because 61a/b/c are often used as the benchmark curricula wise. An entire generation of Californian computer engineers have been RISC-V fluent as a result.
The hivemind assumption that HN's user base is "venture capital", "tech bro", "founders", and "Silicon Valley" is around 5 years out of date.
Anecdotally, the vast majority of younger (below 30) founders, engineers, VCs, and builders in the Bay have either not heard of HN or quit it within weeks due to toxicity.
So, you are calling the author a liar?
> He derives the case for the chip and then spends the rest of the article annoyed that the chip exists. This is almost satirical.
His criticisms are entirely valid, because why can't the the thing that has a free spec and will likely dominate that space ... also be good too? Can't we have all the nice things?
>He derives the case for the chip and then spends the rest of the article annoyed that the chip exists.
>This is almost satirical.
That's all that needs to be said.
It's like comparing Unity and Godot. Unity is better in every single way but one, you have to license it from a very poorly ran company.
You don't "own" your games, they ship with black box spyware. The pricing for using it can change from day to day.
I swear the Unity C level employs a Magic 8 Ball and consults it for key management decisions.
If you need to edit the Unity Engine source code your looking at a secret additional licensing fee which is certainly unaffordable for hobbyist and most indies.
Vs Godot which is completely free under the MIT license.
Everything about the above can be said for ARM as well.
RISC-V is free for everyone to play with. If you think it sucks you can always fork it and jerryrig it to work on existing hardware.
If you have money you can even get custom hardware for your forked RISC-V.
I very much enjoyed reading this article, I'm optimistic in seeing what OPs students come up with. This is life changing technology that's essentially available to all.
I'm not a professional game maker. But having used unity in anger in the past I found Godot a breath of fresh air. What unity really wins with is the unity asset store.
I don't think the Author disagree with what the original article wrote. If anything everything he said seems to reassert what the original article intended to state.
And while things has died down a lot in the past few years, there is a reason why I wrote the line.
"You do not criticise The Rusted Holy Grail and the Riscy Silver Bullet."
To me it feels like the difference in positions is "this could be made better" vs. "but this is already so much better than before". Both are right.
Maybe I'm missing something important so far...
I was thinking the same. RISC-V is certainly impressive and I'm glad we have it, but the original article isn't wrong in its complaints either.
It definitely could have gone with a less abrasive tone (as entertaining as it is), so it's no wonder it's getting some pushback.
Maybe. I'm not sure if the original author's intent was to say how risc-v could be better or to say it is bad and people should use other (proprietary) ISAs instead.
Yeah the complaints in the original article are valid, but it's like complaints about Android or iOS. There are plenty of valid complaints against either, but neither is strictly better than the other.
Nice read!
Though it feels a bit strange that "I have exceeded the allowed number of requests. (500 times)" when I first clicked the article and I'm pretty sure I don't share the ip of my self-hosted VPN with anyone.
Working archived copy - https://archive.is/9FaRC
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A 3rd World Embedded Engineer Learns About Caching Generated HTML The Hard Way.
Original HN discussion referenced:https://news.ycombinator.com/item?id=49298035
Absolutely hugged to death.
My perspective using Nix is that it's hardly worth standardizing ISAs. Recompiling software is easy and we should have a Cambrian explosion of different designs.
This is especially good if one scopes out a family of ISAs that are ABI compatible such that one can compile down to a semi-pre-optimized portable IR, and just do the last bit per ISA.
"Now price the same journey on the other side, forget x86-64 and that duopoly, patent minefield, with multi-thousand dollar debug probes; we'll take a look at ARM."
The 386 and 486 patent should have expired more than 20 years ago. No one tried to open source it. https://github.com/EI2030/Low-power-E-Paper-OS/blob/master/0... There were many companies that had clones in the early 90s, and I wonder whether any of them still have the rights to manufacture them.
" That is a better reason than elegance. and I want to tell Mr Grinberg, that the word priviledge he tosses around in his article also extends beyond the ISA depending on where you are in the world."
Grinberg is an emigre from Ukraine, which isn't the most privileged place in the world. In fact his research articles go deeper than the average software developer in Silicon Valley.
This is the sort of content I endure this place for. Thanks for posting.
You have exceeded the allowed number of requests.
Your Requests: 500 Request Limit: 500 per minute
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with no vpn
I have no idea what's going on here, but the title alone gave me second-hand engineering stress. Solid post.
This blog post is very defensive and argumentative, which I guess is fair considering Dmitry's post is similarly inflammatory, but most of it was really not convincing:
> Simply put, the things a high-end CPU needs are diametrically opposed to the things a small cost-saving microcontroller core needs.
> The conclusion he draws is that no single ISA can serve both ends, and that RISC-V fans are fooling themselves, in theory the premise is true. The conclusion does not follow, and I can show you why from three parts sitting on my desk as we speak.
> CH32V003. This is the cheap "RV32EC" with sixteen registers, no multiplier, no divider, machine mode only,
> CH32H417. A dual core MCU that is unmatched in performance to price point and is at the higher end of the MCU line
> Baochip. A VexRISC-V with an MMU built around a stack thats open from silicon to os Baochip-1x: A Mostly-Open, 22nm SoC for High Assurance Applications
Uh, which one of these is a datacenter server cpu? Or a workstation cpu? Or at least a developer laptop cpu? How about a Raspberry Pi 4 level SBC (supporting latest ubuntu and fedora releases, driving a display that runs a browser and plays video ...)
There's a lot of angry indignation but it seems obvious that Dmitry is quite right about this.
But I found this is where this blog post starts making a lot of sense:
> Has anyone tried adding an MMU to a Cortex-M? The physical tradeoffs are real, the difference is that with RISC-V, the ISA owner does not decide for you where that boundary must be drawn. If you want virtual memory on ARM you license a Cortex-A instead, which is a different core family, a different profile, a different negotiation, and a different royalty.
> Compare what happened with Baochip. The RISC-V privileged specification defines supervisor mode and Sv32 paging as optional things an implementation may provide. VexRISC-V is an open core, somebody added an MMU to it. bunnie built a chip around it and runs a microkernel with real process isolation on it
Yeah, that is a good point. We're still in the low-end specialty realm, but that is real interesting advantage for RISC-V, a good reason for it to exist.
As for shipping to Trinidad and Tobago ... this post is trying too hard to turn this into moral issue, but it seems a bit random (OrangePi cost $30 and shipped free? you can also get arm-based and stuff from the same places), and the vast majority of people don't live on semi-remote islands, it doesn't make sense to consider this kind of accessibility above all else, and it's strange to blame Dmitry for not thinking of you here.
That is just an amazing website and initiative.
https://rvembedded.com/products/project-lab/
Definitely interested!
Beautiful.
I read the "They Should Have Known Better" article and forgot it. I've seen this before. I know it's hot air and does not matter, and I can't afford to worry about things that don't matter.
When I say I've seen this before, I'm talking about ancient history: controversies so old and so laughable that they've been forgotten. When, for example, AMD handed the world AMD64/X86_64, the same things were said: fragmentation, legacy+flawed ISA, etc. That has not aged well, and "They Should Have Known Better" won't either.
The "fragmentation" argument has no merit. The jumble of extension names and profiles in RISC-V are, in fact, direct evidence that RISC-V is succeeding: it's the RISC-V ecosystem aggressively, collaboratively and successfully tackling pain points and solving them. This is what RISC-V is supposed to be doing, and it's doing it, and empires are being built on it.
Take this part: "The existence of CLIC and various proprietary 'fast IRQ' / auto-stacking extensions is an additional indictment."
CLIC is miraculous. It's an advanced embedded interrupt controller, and it's wonderful: it brings the equivalent of ARM's NVIC to RISC-V, except better. You can implement an extremely efficient scheduler that guarantees deadlock-free concurrency: bare-metal, real-time, hardware-accelerated "Fearless Concurrency," on an MCU with no RTOS![1] Its appeal is so great that, despite still being a draft spec, the leading RISC-V MCU designers are adopting it. Espressif's ESP32-S31 has it, for example. The chaotic emergence of this awesome thing is what is condemned as an "indictment."
Speaking of ESP32-S31, it's going to be a monster when silicon becomes available in quantity. This RV Embedded writing mentions MMUs a lot. Guess what? The S31 has an Sv32 MMU. It can run Linux. Not μClinux. Real Linux. It's already been done twice (that I know of) on the Espressif eval boards. People like Armstrong Subero are going to change the world with it.
That's the froth of RISC-V. The ground is shaking, and the peanut gallery of ISA wizards has no power over it. In a few years, after RISC-V has lain waste to our world of proprietary ISAs and Western IP regime rent seeking, "They Should Have Known Better" will look as silly to everyone as it already looks to me.
"Rate Limit Exceeded"
Does anyone have an archive?
More than half the article is AI slop. Sad.
The author of the article just got a fan.
Some serious stuff he builds on top of those chips.
Just an unlucky spawn point. We need to focus on ourselves. "oh no shipping to some remote island is expensive compared to NYC that has next day free on everything" Well, duh.
yo this is actually some really fire reading. i had to read it twice then go back and read the original that he's responding to here. i feel full of wonder right now seeing people who are this deep into compsci debating merits in the marketplace of ideas, there's just so much going on globally with computing that i never even get to see. super fascinating to read about the different constraints at play here even the global socioeconomic ones and how they apply to the chip world in general. it sounds like risc-v's real play is democratizing access to the entire embedded stack