jcalvinowens

6 ms·

61.
by jcalvinowens 6mo ago
One thing people miss is that bugs in open source are much much easier to fix when you catch them right away. You find more bugs when you test aggressively, but the effort per bug is usually significantly lower. I think the key is to diff
62.
by jcalvinowens 6mo ago
Anybody who is interested should read the full report: https://www.faa.gov/sites/faa.gov/files/AirFrance447_BEA.pdf
63.
by jcalvinowens 6mo ago
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 militar
64.
by jcalvinowens 6mo ago
> 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
65.
by jcalvinowens 6mo ago
When you've capitalized the N in "Numa", it's a lot more obvious to my brain you don't mean the acronym. But this is nitpicky bikeshedding and maybe I'm weird :)
66.
by jcalvinowens 6mo ago
I use ~500W of Linux machines to heat a little office, it is perfectly sufficient for California winter.
67.
by jcalvinowens 6mo ago
> This LLVM change has been merged into llvm:main. We also prepared a corresponding GCC patch [5], which is currently under review. Best thing in the paper, bravo :)
68.
by jcalvinowens 6mo ago
This is the moral equivalent of shutting the water off for a whole city because one dude's house has a leak. The harms to society clearly and obviously outweigh any possible benefits to society. But if that one dude has the power to sh
69.
by jcalvinowens 6mo ago
Agreed! But if you can reverse the acquire order, you can structure the function scopes such that you don't need the explicit unlock() calls, which is a bit nicer IMHO.
70.
by jcalvinowens 6mo ago
This reply is word salad that completely fails to engage with anything I've actually said to you... please don't waste my time with more LLM generated comments.
71.
by jcalvinowens 6mo ago
No, the entire point of what I was saying is that big_lock and little_lock are at two different levels.
72.
by jcalvinowens 6mo ago
In the example it seems pretty clear to me that: Mutex::new(AppConfig::default()); ...is meant to be acquiring a mutex protecting some global config object, yes? That's what I'm calling a "global lock". > The
73.
by jcalvinowens 6mo ago
The Level<> abstraction is a really neat way to have your cake and eat it too: you only need a consistent arbitrary order to avoid deadlocks, but the order can have performance consequences when some locks are more coarse than others.
74.
by jcalvinowens 6mo ago
I've been replacing old windows machines with raspberry pi fives for my extended family. They all love them! The cost makes the biggest difference: everybody is resistant, but caves and tries it when I say it only costs $100.
75.
by jcalvinowens 7mo ago
> An elbow bumping a switch [..] really just building tension and storytelling to make the whole post more edgy. A guarded switch, no less. But personally I'm trying to be more generous about this sort of thing: it is very very di
76.
by jcalvinowens 7mo ago
The code was inconsistent with itself: that's not circular. Every path dropped the lock except one.
77.
by jcalvinowens 7mo ago
It's a waste of resources too. I've seen startups waste soooooo much time and effort on simple native apps that could trivially be webviews, it's tragic .
78.
by jcalvinowens 7mo ago
I'm asleep and I misread that as 10cm. Thanks.
79.
by jcalvinowens 7mo ago
I think they're claiming the actual transmit power is 240W (23.8 dBW), and the EIRP is 63.1 dBW. I am sort of skeptical of the claimed gain... even at 6GHz, you need a 2-meter parabolic reflector to get 40dB, the array is 1/10th t
80.
by jcalvinowens 7mo ago
> Getting a 1.5 kW, 240-antenna EME array It says 1W TX power per antenna. So the 240 antenna array which draws 1500W has a transmit power of 240W.
81.
by jcalvinowens 7mo ago
Sure. But if you squint even that isn't good enough, you'll still take interrupts on that core in the critical section sometimes when somebody else wants the lock. The other problem with spin-wait is that it overshoots, especially
82.
by jcalvinowens 7mo ago
> Default to the smallest thing that could possibly work This is the key. I feel like the other 17 points all happen naturally if you heed this one. "Release early, release often"
83.
by jcalvinowens 7mo ago
> Turns out to be pretty crucial for performance though... I don't doubt it. I just meant nasty with respect to using futex() to sleep instead of spin, I was having some "fun" trying. I can certainly see how pushing that s
84.
by jcalvinowens 7mo ago
It doesn't matter, it's a long tail thing: on average user spinlocks can work, and even appear to be beneficial on benchmarks (for many reasons, Andy alludes to some above). But if you have enough users, some of them will experi
85.
by jcalvinowens 7mo ago
That 64-bit atomic in the buffer head with flags, a spinlock, and refcounts all jammed into it is nasty . And there are like ten open coded spin waits around the uses... you certainly have my empathy :) This got me thinking about 64-bit fu
86.
by jcalvinowens 7mo ago
> I feel like using spinlocks in user space at all without kernel support like rseq is just asking for weird performance degradations. Yeah, exactly. "Doctor, help, somebody replaced my wooden hammer with a metal one, and now I can&
87.
by jcalvinowens 7mo ago
It is truly unbelievable. A 2x32GB DDR5 kit I paid $150 for last July is listed for $885 today. Even DDR4 is getting hit, a 2x16GB kit I paid $105 for a year ago is $230 today.
88.
by jcalvinowens 7mo ago
People saying "the FOWARD chain defaults to ACCEPT" are missing the deeper point: with the kconfig most distros use, the filtering code doesn't even exist at all until you load the kernel modules! At the lowest level, it is i
89.
by jcalvinowens 7mo ago
Somebody has to actually write the code at some point, it can't be serialization abstractions all the way down. That's what I'm talking about.
90.
by jcalvinowens 7mo ago
I read your reply as mostly agreeing with me: endianness is arbitrary, using big endian for a novel protocol just because some widely used protocols decided to decades ago is silly. > it’s easier to draw pictures as a matrix of bytes tha

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