[HN Gopher] Tracking down a 25% Regression on LLVM RISC-V
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Tracking down a 25% Regression on LLVM RISC-V
Author : luu
Score : 128 points
Date : 2026-04-12 19:52 UTC (2 days ago)
(HTM) web link (blog.kaving.me)
(TXT) w3m dump (blog.kaving.me)
| brcmthrowaway wrote:
| This really shouldn't be free work.
| Jyaif wrote:
| Folks that do this work for "free" do it because they enjoy it.
|
| And a small observation: if you require money to do something,
| you usually have no chance of being as good as the folks that
| do it for the pleasure.
| cjbgkagh wrote:
| I would suggest that's an availability bias, those who do it
| for free are more likely to blog about it.
|
| There is a common distinction between professional and
| amateur with the former getting paid for their work. In
| general there is an understanding that someone getting paid
| can focus and do it full time and are expected to be better
| than someone who does it as a hobby.
|
| Perhaps coding is an unusual space where the best coders are
| often misfits who have a hard time holding down a job.
| luqtas wrote:
| i think you need to understand more about modern software
| infrastructure [0]
|
| [0]
| https://www.fordfoundation.org/learning/library/research-
| rep...
| cjbgkagh wrote:
| I'm focusing on the following premise;
|
| > if you require money to do something, you usually have
| no chance of being as good as the folks that do it for
| the pleasure
|
| Not only do I think professional have a chance to be as
| good as amateurs, but the elite professionals are on
| average better than the elite amateurs.
|
| I do think that we would be better off if more elite
| amateurs became elite professionals.
| luqtas wrote:
| should i repeat my comment and link the free document i
| doubt you read, again? modern software infrastructure
| runs on "folks that do it for the pleasure"
| cjbgkagh wrote:
| I did read it and I agree with the sentiment, but
| disagree that professionals have no chance to reach the
| level of amateurs.
| rcxdude wrote:
| Modern software infrastructure also relies on a lot of
| professionals.
| jcalvinowens wrote:
| > In general there is an understanding that someone getting
| paid can focus and do it full time and are expected to be
| better than someone who does it as a hobby.
|
| For something like flying airplanes, I think this is
| obviously true: nobody can afford to spend the required
| hours doing it unless somebody else is paying for the
| airplane, and the only way that happens is if that person
| is your employer. A lot of things are like that.
|
| But programming is very different, it requires almost no
| resources to practice except your time. You can sit at home
| in your pajamas with $1K worth of hardware and keep
| yourself busy for a lifetime through open source. Of
| course, you can also spend a lifetime building useless
| sandcastles while telling yourself you're a genius: you
| have to find ways to hold yourself accountable to grow.
|
| I've been fortunate to get paid to work on some interesting
| things... but the work I do for fun is, on average, ~100x
| more challenging and interesting than the work I'm paid to
| do. I would be a much much less capable programmer if I'd
| only done work I was paid to do for the past decade.
|
| I wouldn't go so far as to say "amateurs are better than
| professionals", but I think the skill level of the two
| groups is much more blurred in programming than in most
| other things.
| NetMageSCW wrote:
| Your example is obviously false; there are 500K GA pilots
| in the US alone varying from my friend who had a Cessna
| 172 and flew it regularly (until joining CAP) to John
| Travolta flying his own 737.
| cjbgkagh wrote:
| And how would John Travolta at roughly 5K lifetime hours
| compare to the best of the comercial pilots at 1K hours
| per year? Also John Travolta has a commercial licence and
| has been paid to fly.
|
| This argument seems absurd to me.
|
| I get that in software quite often time is wasted by poor
| management that otherwise would not be wasted if working
| unpaid. Well managed research orgs can work at elite
| levels but they are few and far between.
| brucehoult wrote:
| Not all flight hours are equal.
|
| Airline pilots rack up a lot of hours but get very little
| "stick time", and what they do get is extremely sedate
| flying to not scare the passengers / spill their drinks.
| Their primary skills are pushing buttons on the autopilot
| and talking in the radio and transcribing clearances.
|
| A military pilot gets more effective stick time. But
| aerobatic pilots, ag pilots (but I repeat myself), and
| glider pilots gain a LOT more experience and skill per
| hour flown than an airline pilot.
|
| I mean, just look at this glider flying lesson:
|
| https://www.youtube.com/watch?v=MJapUCeDeOI
| cjbgkagh wrote:
| I was working with the example given which was weak on
| two points, John Travolta gets paid and while his hours
| are impressive they nowhere near full time professional
| hours.
|
| Military pilots are also professionals, and of the glider
| pilots how many of the best are trainers. Ag pilots are
| professionals, as are helicopter mustering pilots who are
| incredibly skilled. The majority of acrobatic pilots are
| also professional pilots. I'm not suggesting that great
| amateurs don't exist just that a great amateur who has
| gone pro can often beat one that hasn't.
|
| I understand the sentiment, on one hand if I was rich I
| would be able to devote my time into constant
| improvement, but then maybe I wouldn't have the same
| drive to succeed as having my livelihood dependent on the
| outcome. There is institutional knowledge gained by
| working in a research org that would be hard to replicate
| as an independent scientist.
| brucehoult wrote:
| I've been a gliding instructor, sometimes doing up to ten
| flights a day, all summer (e.g. when I was unemployed for
| a time). In the NZ/Aus/UK style clubs you don't get paid
| for it, but then it doesn't cost you anything either.
| cjbgkagh wrote:
| I'll grant that glider flight instructor are probably
| among the best pilots in the world, even if unpaid.
| jcalvinowens wrote:
| I have a pilot's license, that's why I choose that
| example. What I'm saying is that I cannot possibly fly
| enough for fun in my remaining life to have comparable
| skill to a professional pilot who flys full time for the
| military or for an airline.
|
| Somebody wealthy enough can afford to just pay to fly
| that much, I guess, but that's so few people it's not
| even worth mentioning as a possibility.
| kubb wrote:
| Sure but then they have to waste time working for money,
| rather than doing God's work.
| MiguelX413 wrote:
| Wonderful way to put it.
| mathisfun123 wrote:
| > if you require money to do something, you usually have no
| chance of being as good as the folks that do it for the
| pleasure.
|
| ......... o.O i guess the professional football leagues all
| have players who are _worse_ than the rec leaguers? hners are
| delusional...
| tester756 wrote:
| >And a small observation: if you require money to do
| something, you usually have no chance of being as good as the
| folks that do it for the pleasure.
|
| Usually complex things are there, where they money is -
| semiconductor industry, big corpos (chromium, linux, llvm,
| etc), AI, etc.
| jeffbee wrote:
| Why not though? The entirety of the LLVM project is available
| to them, and you, for free, as is the RISC-V ISA itself. A lot
| of people are getting a lot of value from free and open
| software, and they may feel their contributions are in a like
| spirit.
| themafia wrote:
| There should be a medal we can give out to people who do
| anyways.
| LoganDark wrote:
| The medal is called a corporation that makes thousands or
| more off their work without paying anything back.
| szmarczak wrote:
| SVGs on Firefox are broken (like 0.1% of the size it needs to
| be).
| LeFantome wrote:
| This could have been a story about any ISA but it warms my heart
| to see RISC-V optimizations like this appearing bit by bit every
| day.
|
| RISC-V chips that are fast enough to get used are appearing now
| and, when they do, the software ecosystem is going to be ready to
| meet it.
|
| In the past, the hardware usually came first with the software
| slow to appear after. This time, it is happening the other way
| around.
| AymanB wrote:
| Thanks for the blog, I really enjoyed it. Good work. This just
| makes me appreciate and love compilers even more, they are a
| fascinating piece of software.
| charcircuit wrote:
| You can hook these benchmarks up to AI and it can automatically
| find and fix these regressions.
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