<rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Hacker News: pjdesno</title><link>https://news.ycombinator.com/user?id=pjdesno</link><description>Hacker News RSS</description><docs>https://hnrss.org/</docs><generator>hnrss v2.1.1</generator><lastBuildDate>Mon, 22 Jun 2026 22:27:10 +0000</lastBuildDate><atom:link href="https://hnrss.org/user?id=pjdesno" rel="self" type="application/rss+xml"></atom:link><item><title><![CDATA[New comment by pjdesno in "The Competitive Moat That AI Can't Replicate"]]></title><description><![CDATA[
<p>Note that for the businesses mentioned in the article, the service <i>is</i> the product.<p>I don't care about service at a gas station - I want to fill my tank, pay, and get out. It's different when I take it to the mechanic - it's a rather old car, and I appreciate them talking intelligently about what the options are and what repairs they would suggest.</p>
]]></description><pubDate>Wed, 17 Jun 2026 22:16:54 +0000</pubDate><link>https://news.ycombinator.com/item?id=48577717</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48577717</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48577717</guid></item><item><title><![CDATA[New comment by pjdesno in "Investigating how prompt politeness affects LLM accuracy (2025)"]]></title><description><![CDATA[
<p>Note that there are a fair number of native speakers of English in Nigeria - more than in all but 3 or 4 US states.<p>In addition, "non-native" English speakers in India (and Nigeria?) typically study English from the first grade, and in many cases attended elementary schools where English was the language of instruction.<p>I think the differences between US English and both Indian and Nigerian English have more to do with divergent evolution of the educational systems. British English has a lot of differences, too, but we don't notice it as much unless we run across things like "whilst", probably because there's more media crossover. (if you find yourself reading Thomas the Tank Engine to kids it jumps out at you, though - the entire vocabulary for railroads evolved during a period when US and British English were diverging)</p>
]]></description><pubDate>Thu, 28 May 2026 15:05:55 +0000</pubDate><link>https://news.ycombinator.com/item?id=48309998</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48309998</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48309998</guid></item><item><title><![CDATA[New comment by pjdesno in "Five frontier LLMs disagree on 67% of 1k real-world fact-check claims"]]></title><description><![CDATA[
<p>They overstate their results in the headline.<p>In section 2, 34% of cases are found to have "substantive" disagreements differing by 2 or more buckets - True + Misleading, Mostly True + False, or True + False.<p>This is probably a better measure than the headline one. It's still a concerning fraction, although some fraction is no doubt due to forcing "I don't know" cases to return an answer anyway.</p>
]]></description><pubDate>Thu, 28 May 2026 14:47:04 +0000</pubDate><link>https://news.ycombinator.com/item?id=48309725</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48309725</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48309725</guid></item><item><title><![CDATA[New comment by pjdesno in "White Rabbit – sub-nanosecond synchronization for large distributed systems"]]></title><description><![CDATA[
<p>If you run "make" in the papers/IBIC2013 directory you'll get this paper:
<a href="https://cds.cern.ch/record/1743073/files/thbl2.pdf" rel="nofollow">https://cds.cern.ch/record/1743073/files/thbl2.pdf</a><p>It's quite interesting - this isn't ethernet as we know it. Instead of each NIC using its own free-running clock, all the physical layers are sync'ed to each other at layer 1. (note that gigabit ethernet, which is what it uses, sends data at all times - when idle it sends the idle symbol)</p>
]]></description><pubDate>Mon, 25 May 2026 04:51:27 +0000</pubDate><link>https://news.ycombinator.com/item?id=48263494</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48263494</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48263494</guid></item><item><title><![CDATA[New comment by pjdesno in "The memory shortage is causing a repricing of consumer electronics"]]></title><description><![CDATA[
<p>"I wonder if this is actually true in the long-term though. If they were to flood the market with lots of high capacity memory, then I think our programs would start using more memory too. As a result we might end up needing more memory faster compared to if they keep demand unmet."<p>It's a gambler's ruin problem. Future profits are worth zero if you go out of business first.</p>
]]></description><pubDate>Fri, 22 May 2026 15:51:39 +0000</pubDate><link>https://news.ycombinator.com/item?id=48237522</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48237522</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48237522</guid></item><item><title><![CDATA[New comment by pjdesno in "The memory shortage is causing a repricing of consumer electronics"]]></title><description><![CDATA[
<p>Jatin Malek on Twitter had perhaps the best explanation of the DRAM crunch:<p>"The reason why RAM has become four times more expensive is that a huge amount of RAM that has not yet been produced was purchased with non-existent money to be installed in GPUs that also have not yet been produced, in order to place them in data centers that have not yet been built, powered by infrastructure that may never appear, to satisfy demand that does not actually exist and to obtain profit that is mathematically impossible."</p>
]]></description><pubDate>Fri, 22 May 2026 15:49:30 +0000</pubDate><link>https://news.ycombinator.com/item?id=48237492</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48237492</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48237492</guid></item><item><title><![CDATA[New comment by pjdesno in "Building a web server in aarch64 assembly to give my life (a lack of) meaning"]]></title><description><![CDATA[
<p>> I’m curious what the performance of this implementation is<p>Almost certainly crap.<p>As the author states, it's a simple fork-on-request server, which was state-of-the-art in about 1996. But that's not the point.</p>
]]></description><pubDate>Mon, 11 May 2026 19:13:34 +0000</pubDate><link>https://news.ycombinator.com/item?id=48099364</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48099364</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48099364</guid></item><item><title><![CDATA[New comment by pjdesno in "Discovering hard disk physical geometry through microbenchmarking (2019)"]]></title><description><![CDATA[
<p>Also note “Disks are like snowflakes - no two are alike”, Krevat, Tucker & Ganger, HotOS 2011. The number of tracks and bit density is not the same on different surfaces within the same disk, or across disks of the same model.<p><a href="https://www.usenix.org/legacy/event/hotos11/tech/final_files/Krevat.pdf" rel="nofollow">https://www.usenix.org/legacy/event/hotos11/tech/final_files...</a></p>
]]></description><pubDate>Tue, 05 May 2026 03:48:31 +0000</pubDate><link>https://news.ycombinator.com/item?id=48017840</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48017840</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48017840</guid></item><item><title><![CDATA[New comment by pjdesno in "Discovering hard disk physical geometry through microbenchmarking (2019)"]]></title><description><![CDATA[
<p>Read this paper: “ Revisiting HDD Rules of Thumb: 1/3 Is Not
(Quite) the Average Seek Distance”, MSST 2024. 
<a href="https://www.msstconference.org/MSST-history/2024/Papers/msst24-1.1.pdf" rel="nofollow">https://www.msstconference.org/MSST-history/2024/Papers/msst...</a><p>It has a very good approximation for seek time based on the track radius delta, with experimental validation on a modern drive.</p>
]]></description><pubDate>Tue, 05 May 2026 03:45:02 +0000</pubDate><link>https://news.ycombinator.com/item?id=48017820</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=48017820</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=48017820</guid></item><item><title><![CDATA[New comment by pjdesno in "Backblaze has stopped backing up OneDrive and Dropbox folders and maybe others"]]></title><description><![CDATA[
<p>Why should Backblaze back up their competitors’ data? And what use is it to you for it to do so?</p>
]]></description><pubDate>Tue, 14 Apr 2026 13:56:06 +0000</pubDate><link>https://news.ycombinator.com/item?id=47765725</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47765725</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47765725</guid></item><item><title><![CDATA[New comment by pjdesno in "Veracrypt project update"]]></title><description><![CDATA[
<p>Interesting.<p>My only experience with Veracrypt is via a law firm I was consulting with, who used it to protect some files they were sharing with me. Law firm and their end client are both big, prestigious companies.</p>
]]></description><pubDate>Wed, 08 Apr 2026 18:25:14 +0000</pubDate><link>https://news.ycombinator.com/item?id=47694244</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47694244</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47694244</guid></item><item><title><![CDATA[New comment by pjdesno in "Škoda DuoBell: A bicycle bell that penetrates noise-cancelling headphones"]]></title><description><![CDATA[
<p>It's a soda bottle - it fits in your water bottle holder, and you can replace it for a couple of bucks if it fails. 80 psi is pretty low pressure (typical narrow tires are 100-120) and the bottle itself is very low mass, so the fabric around the bottle should ensure safety if it bursts.<p>IIRC these came out in the early-mid 90s; a bike messenger trick at the time was to fasten the horn to your handlebars with velcro, so you could take it off and hold it near a car window when triggering it.</p>
]]></description><pubDate>Wed, 08 Apr 2026 18:11:52 +0000</pubDate><link>https://news.ycombinator.com/item?id=47694084</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47694084</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47694084</guid></item><item><title><![CDATA[New comment by pjdesno in "A $20/month user costs OpenAI $65 in compute. AI video is a money furnace"]]></title><description><![CDATA[
<p>Look up the Osborne 1, the first "portable" (i.e. luggable) computer. They went out of business not only because they lost money on each unit, but because of how many they sold. Then they pre-announced their next model, which killed all demand for the existing one, and they were toast.</p>
]]></description><pubDate>Thu, 02 Apr 2026 20:47:03 +0000</pubDate><link>https://news.ycombinator.com/item?id=47619942</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47619942</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47619942</guid></item><item><title><![CDATA[New comment by pjdesno in "Optimizing a lock-free ring buffer"]]></title><description><![CDATA[
<p>I don't actually get your point.<p>You dismissed the standard lock-guarded data structure as a "bogus comparison", despite it being the way every programmer is taught to write multi-threaded code.<p>Now the more you write, the more you seem to make the case that (a) normal programmers shouldn't be writing code like this, and (b) there are significant speedups possible if someone who knows what they're doing *does* write a highly tuned lock-free library.</p>
]]></description><pubDate>Fri, 27 Mar 2026 21:30:10 +0000</pubDate><link>https://news.ycombinator.com/item?id=47548519</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47548519</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47548519</guid></item><item><title><![CDATA[New comment by pjdesno in "Optimizing a lock-free ring buffer"]]></title><description><![CDATA[
<p>It's not a "bogus and misleading baseline".<p>It's precisely the way we teach people how to build thread-safe systems. And we teach them to do it that way because we've learned from experience that letting them code up their own custom synchronization primitives leads to immense woe and suffering.<p>(and it's not slow because of the C++ mutex implementation, either - I tested a C/pthreads version, and it was the same speed as the C++ version)</p>
]]></description><pubDate>Fri, 27 Mar 2026 19:35:36 +0000</pubDate><link>https://news.ycombinator.com/item?id=47547218</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47547218</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47547218</guid></item><item><title><![CDATA[New comment by pjdesno in "Optimizing a lock-free ring buffer"]]></title><description><![CDATA[
<p>What's not guaranteed for "normal" loads and stores on many architectures is the order in which writes become visible to other CPU cores.</p>
]]></description><pubDate>Fri, 27 Mar 2026 16:17:42 +0000</pubDate><link>https://news.ycombinator.com/item?id=47544690</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47544690</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47544690</guid></item><item><title><![CDATA[New comment by pjdesno in "Optimizing a lock-free ring buffer"]]></title><description><![CDATA[
<p>That's what "lock-free" means. You still need to use the hardware mechanisms provided for atomicity.<p>The whole point of lock-free data structures and algorithms is that sometimes you can do better by using these atomic operations inside your own code, rather than using a one-size-fits-all mutex based on those same atomic operations.<p>(Note that I say "sometimes". Too many people believe that lock-free structures are always faster; as always, your mileage may vary. In this case it's a huge win, to the point where I would bet it almost always moves the bottleneck to the code actually using the ring buffer.)</p>
]]></description><pubDate>Fri, 27 Mar 2026 16:15:47 +0000</pubDate><link>https://news.ycombinator.com/item?id=47544670</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47544670</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47544670</guid></item><item><title><![CDATA[New comment by pjdesno in "False claims in a widely-cited paper"]]></title><description><![CDATA[
<p>I would point out that most products are useless, and either fail or replace other products which weren't any worse. None of which prevented me from cashing my paychecks for the first half of my career when I worked in private industry.<p>Most scientific research represents about the same amount of improvement over the state of the art as the shitty web app or whatever that you're working on right now. It's not zero, but very few are going to be groundbreaking. And since the rules are that we all have to publish papers[*], the scientific literature (at least in my field, CS) looks less like a carefully curated library of works by geniuses, and more like an Amazon or Etsy marketplace of ideas, where most are crappy.<p>[* just like software engineers have to write code, even if the product ends up being shitty or ultimately gets canceled]<p>Neither of us are going to be changing how the system works, so my advice is to deal with it.</p>
]]></description><pubDate>Thu, 26 Mar 2026 04:01:48 +0000</pubDate><link>https://news.ycombinator.com/item?id=47526510</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47526510</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47526510</guid></item><item><title><![CDATA[New comment by pjdesno in "False claims in a widely-cited paper"]]></title><description><![CDATA[
<p>Are there any factual allegations on that page? All I could find was "the method described in the paper is not the method the authors actually used", without any elaboration.<p>I'll add that the reaction of most of academia will be "It's in a management journal - of course it's nonsense."</p>
]]></description><pubDate>Thu, 26 Mar 2026 03:52:30 +0000</pubDate><link>https://news.ycombinator.com/item?id=47526463</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47526463</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47526463</guid></item><item><title><![CDATA[New comment by pjdesno in "Data centers are transitioning from AC to DC"]]></title><description><![CDATA[
<p>90% of the power in our academic data center goes 13.8kV 3-phase -> 400v 3-phase, and then the machines run directly from one leg to neutral (230v). One transformer step, no UPS losses, and the server power supplies are more efficient at EU voltages.<p>But what about availability? If you ask most of our users whether they’d prefer 4 9s of availability or 10% more money to spend on CPUs, they choose the CPUs. We asked them.<p>There are a lot of availability-insensitive workloads in the commercial world, as well, like AI training. What matters in those cases is how much computing you get done by the end of the month, and for a fixed budget a UPS reduces this number.</p>
]]></description><pubDate>Wed, 25 Mar 2026 13:18:29 +0000</pubDate><link>https://news.ycombinator.com/item?id=47516964</link><dc:creator>pjdesno</dc:creator><comments>https://news.ycombinator.com/item?id=47516964</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=47516964</guid></item></channel></rss>