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finnh

> Enabling allocation sampling profiling with a sampling period of 4 MB leads to a maximum time overhead of 25% in our benchmarks, over un-profiled regular execution

25% is not low overhead, but perhaps this example is the worse case and other tunings actually are low overhead. There's no exact definition I don't think, but anything much over 3% starts to feel like a lot of overhead to me.

Reading on:

> Our main technical insight is that the check whether an allocation should be sampled can be made free. This is done by folding it into the bump-pointer allocator check that PyPy’s GC uses to find out if it should start a minor collection. In this way the fast path with and without memory sampling are exactly the same.

That is cool, and means you only pay for the samples you produce = something you could leave enabled confidently, with a low-enough sample rate at least.

Re:It's True: The Jaws Shark Is Public Domain on Friday June 20, 2025 @04:36PM (#44331845)
> He went to the Museum of Natural History to study sharks, and he had a model pose across a couple of stools for reference of what someone looks like swimming.

That explains why the swimmer, at least, looks a bit fake.

"trivial ... serious efforts"

which is it? you contradict yourself in a single sentence.

It's also unclear how the first graph, whose y-axis is labelled "req/s", is showing a latency spike. Latency is not visible on that graph, AFAICT, only throughput.
exactly. that one clause casts doubt on all the other reasoning; randomization controls for patient selection bias but not diurnal clinic performance
Re:Square Theory on Tuesday May 27, 2025 @01:48PM (#44109144)
My family calls that game "pink mink"!
Re:A programming language made for me on Tuesday May 13, 2025 @11:52AM (#43974286)
I'm with you here. The whole diatribe falls firmly under "tell me you've never needed to write performant code without telling me you've never needed to write performant code..."
Re:Accountability Sinks on Saturday May 03, 2025 @09:16AM (#43878861)
What's funny is that checklists in hospitals have been shown, empirically, to be massive life-saving devices.

cyber perhaps not so much...

Re:Accountability Sinks on Saturday May 03, 2025 @09:13AM (#43878842)
s/show/department/
Re:No as a Service on Wednesday April 30, 2025 @10:48AM (#43846041)
ah, yes, the "memory is no object" way of obtaining a weighted distribution. If you need that sweet sweet O(1) selection time, maybe check out the Alias Method :)
(not a worthy comment, but)

I really like the free lunch / free launch pun here, intentional or not.

Re:Getting Forked by Microsoft on Monday April 21, 2025 @02:03PM (#43754679)
"fantasizing about a collab" sounds like the world of sneakers, not software. What does that even mean in the world of software?
Re:Show HN: K(r)ep - A high-performance string search utility on Wednesday April 16, 2025 @01:50PM (#43708365)
With this comment showing that search was inconsistent and gave incorrect results: https://news.ycombinator.com/item?id=43335277

why the repost?

Re:Kezurou-Kai #39 on Monday April 14, 2025 @03:11PM (#43684986)
That room must have smelled amazing. I want to go hang out there.
Is it common to abbreviate Wittgenstein to "Witt"? Don't recall seeing/hearing that before, but it's been awhile since undergrad.
Do you have any examples of defamation lawsuits? I've sold two companies, and have plenty of rich and upper-level exec friends, and I have never heard of a defamation lawsuit amongst tech execs.

There is definitely a stupid game where people don't tell it like it is, but in my experience it's because people don't want to deal with HR at all, and so don't do or say anything that might bring a tut-tut from HR. Because people in HR are beyond annoying...

And HR fears a wrongful-termination lawsuit, not a defamation lawsuit.

This is all in the US, though. The UK has quite different libel laws and so maybe lawsuits are more common there.

Re:Gemini Robotics brings AI into the physical world on Wednesday March 12, 2025 @02:21PM (#43346168)
Of course, we already live in this reality - just substitute "Corporation" for "AI".
> I'm increasingly convinced this is a generational thing

You are taking about gas cars, though. Nobody, of any generation, has "range anxiety" in a gas car. People might be afraid they will hit empty, or not trust their fuel gauge, but that's not "range anxiety" that's "running out of gas is a PITA". Those things are different, one is a commonplace that has always been true and the other is new and EV-specific for good reason.

An EV is much harder to recover from an empty battery than an ICE car is from an empty tank. There is no red jerry can you can fill that will give an EV the 10-30 miles you get from a gallon of gas, and there is no guarantee that a refueling station is close by and conveniently located. And ofc if your EV is empty, it will take hours to refill. Hence range anxiety.

I have an EV, I love it and have done 7 hour road trips with it no problem, but planning the battery charge level is something you have to think about in a way that is qualitatively different than with gas cars.

Re:AI Slop, Suspicion, and Writing Back on Sunday January 26, 2025 @11:30AM (#42831239)
> Dismissing all LLM assistance because of some purity dance you want to enact is silly

That's not what I was saying. I was expressing surprise at the lack of spell- or grammar-check in a blog post about detecting slop. I think an AI would generate better text than that of the post, and I'm wondering if the errors are purposeful signifiers of "hey this was a human writing. this busted sentence"

Re:AI Slop, Suspicion, and Writing Back on Sunday January 26, 2025 @12:54AM (#42828036)
> To be clear, I fault no one for augmenting their writing with LLMs. I do it. A lot now. It’s a great breaker of writers block. But I really do judge those who copy/paste directly from an LLM into a human-space text arena. Sure, take sentences – even proto-paragraphs – if they AI came up with something great.

I guess the sloppy writing ("I do it. A lot now" and "if they AI came up with") made me stop reading early, but: is this part of some big reveal? Sloppy grammar as a sign of not-AI? But it's still slop.

Re:Lightcell: An engine that uses light to make electricity on Friday January 17, 2025 @02:33PM (#42742323)
The energy densities listed are flagged as approximate, so grains of salt etc, but the numbers on the page aren't entirely consistent.

The stated energy density is "> 500 watthours/liter".

But higher on the page we see a relative-energy-density bar graph shows lightcell at 5x the energy density of lithium batteries, and (38/5 =) 7.6x less dense then petrol. This implies an energy density for lightcell of 1250 Wh/liter, as (according to Google) petrol clocks in just under 9500 Wh/liter, and (again according to Google) lithium batteries can reach 300 Wh/liter so let's call it 250 for the math to work out.

I'm curious which number is closer to truth: 500Wh/liter, or 1250? Is 1250 the theoretical max and 500 the current output in a test rig?

> Fireproofing isnt mandatory, so people dont do it

100%

> and they hate spending even one dollar extra on roofing when they know a taxpayer-backed insurance policy will cover their substandard construction

That just doesn't follow. More likely is that people building the homes (possibly on spec) are motivated by their bottom dollar, so only do what is mandatory (per your first point) or that people who own the homes simply _don't know about these mitigations_.

Blaming all behavior on a last-resort insurance fund misses a lot of steps between, and I don't think tracks to how people actually behave in the real world.

Re:Flattening ASTs (and Other Compiler Data Structures) on Friday January 10, 2025 @08:46PM (#42662547)
The sample flat program in the post is exactly RPN, no?
Re:Magic/tragic email links: don't make them the only option on Wednesday January 08, 2025 @10:34AM (#42635271)
Wow - i even saw the words "default browser app" and did not even realize it was a setting choice. That works - thank you!

wrt reason : I think that the webview has cookie isolation from the actual app, so using the webview is a bit more privacy-protective. Google being Google that seems unlikely to be the motivating reason, but who knows what good may lurk in the heart of men...

Re:The Evaporative Cooling Effect in Social Networks on Tuesday January 07, 2025 @05:35PM (#42628510)
Doesn't this complaint assume a strict stack-ranking of contributors, where the "top" person has no reason to stay and thus leaves, and then the new top does the same, etc?

Which is not at all how actual humans and relationships work. We each bring different value to the table, along multiple dimensions.

Re:Magic/tragic email links: don't make them the only option on Tuesday January 07, 2025 @05:22PM (#42628394)
where? i just went through Settings > Apps > Gmail on my iphone and found nothing about this. Likewise the in-app Settings in the GMail app lets you choose which browser is the "default app" but it's already set to Safari (the other options are Chrome, by Google, and ... Google, by Google). But that uses an embedded Safari instance inside gmail, not the phone's Safari app.
Re:Cannabis pollen dispersal across the United States on Thursday December 19, 2024 @07:06PM (#42467080)
And yet Headband really did feel like you were wearing a headband =)
Re:Firenvim – Turn the browser into a Neovim client on Thursday December 19, 2024 @02:17PM (#42464772)
Yeah, and the Chrome store is warning about removing it from the store for some best practice violation (no doubt related to the years-since-last-commit).

It does, however, work great for me so :fingers-crossed: I can avoid re-shaving this yak for another few years.

The recent Shōgun series was surprisingly good, I really enjoyed it.

Clavell famously has no idea how to end a book - they pretty much _all_ have a deus ex machina in the form of a natural disaster - but they are excellent & fun reads of the days & weeks leading up to it.

ayeeya, cow chillo

Re:Firenvim – Turn the browser into a Neovim client on Thursday December 19, 2024 @11:35AM (#42463106)
I'm a long-time fan of the Wasavi extension for Chrome/Firefox/Opera, which looks quite similar in terms of user experience. Wasavi is a purely javascript implementation of the vim editing experience, so I believe ends up with a simpler executable model vs launching nvim locally & then bridging to it.

It doesn't have 100% compatibility with vim - no vimscript, for example - but it covers more than enough of the basic movement commands & mappings to be entirely productive for me. I don't know if I would write actual pages of code in it, but I gratefully use it to write long queries in the browser.

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