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Dan Luu
5,594 posts
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Dan Luu

@danluu
Active on mastodon.social/@danluu; also trying out bsky.app/profile/da. No longer read replies or notifications here now that tweetdeck is gated.
danluu.com
Joined December 2008
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    Dan Luu
    @danluu
    Dec 24, 2017
    Computer latency: 1977-2017 danluu.com/input-lag/
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    Dan Luu
    @danluu
    Aug 21
    There's no reason for software to be slow anymore: danluu.com/perf-opt/
    The other day, I saw a viral tweet saying that people talking about how LLMs are causing slow, bloated, code are going to eat crow once they re-write everything in super-optimized assembly. We're not quite at the point where we want to write everything in assembly, but some variant of what Nolan Lawson said about testing, you can choose how many bugs you want now, which I less eloquently noted here, is becoming more true for performance.

In response to a comment in my last post that the cost of formerly specialized performance work has dropped by many orders of magnitude and performance work that used to require a person or team that had a rare set of skills can be done by anyone who can type a few sentences1, which means that you can do all sorts of optimizations that used to be too expensive to be worthwhile for all but the largest scale or most lucrative projects, Marc Brooker responded with

    Completely agree with your closing point. Dynamic custom software, fitted to a part...
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    Dan Luu
    @danluu
    Aug 17
    The benchmarkpocalypse: danluu.com/benchpocalypse/
    There's been a lot of talk about the vulnpocalypse, to which I don't have much to add because I'm not a security person, but I haven't seen much discussion on the closely related (and to be fair, less serious, issue), the benchmarkpocalypse.

While it's become easier than ever to make serious performance gains, it's also become easier than ever to reward hack a benchmark and make fake performance gains. The former is probably happening quietly across many different companies, but the latter is something I see at least once a week nowadays. Someone will claim they optimized X and got some huge performance improvement over existing software, but, when you look at it, what they did was make some optimization that improves benchmark performance without actually improving real-world performance. This is often some kind of "we rewrote X in Rust"1 project or a new startup that's looking to either fundraise or sell something, but it happens on other kinds of projects as well2.

Rather than ...
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    Dan Luu
    @danluu
    Aug 10
    What programming languages are coding agents best at? danluu.com/pl-tokens/
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    Dan Luu
    @danluu
    Jul 24
    Exercises in evals and benchmarking: DeepSWE / Senior SWE-Bench, performance math, and cold weather tires danluu.com/exercise-7/
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