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SynasterBeiter commented on The Weird Concept of Branchless Programming   sanixdk.xyz/blogs/the-wei... · Posted by u/judicious
MontyCarloHall · 5 months ago
This great video [0] demonstrates how CPU performance has only increased 1.5-2x over the past 15(!) years when executing extremely branchy code. Really shows you just how deep modern CPU pipelines have become.

The video also showcases a much more impressive branchless speedup: computing CRC checksums. Doing this naïvely with an if-statement for each bit is ~10x slower than doing it branchless with a single bitwise operation for each bit. The author of the article should consider showcasing this too, since it's a lot more impressive than the measly 1.2x speedup highlighted in the article. I assume the minimal/nonexistent speedups in the article are due to modern CPU branch prediction being quite good. But branch predictors inherently fail miserably at CRC because the conditional is on whether the input bit is 1 or 0, which is essentially random.

[0] https://www.youtube.com/watch?v=m7PVZixO35c

SynasterBeiter · 5 months ago
The linked video doesn't take into account power consumption of these CPUs. He seems to be comparing laptop CPUs, NUC CPUs and desktop CPUs. If you compare a 100W CPU and a 30W CPU that's a couple of years newer, you shouldn't be surprised there isn't much of a difference in performance.
SynasterBeiter commented on Writing Speed-of-Light Flash Attention for 5090 in CUDA C++   gau-nernst.github.io/fa-5... · Posted by u/dsr12
sigmoid10 · 7 months ago
Pytorch now has native support for the Blackwell architecture:

https://pytorch.org/blog/pytorch-2-7/

SynasterBeiter · 7 months ago
It does, but the performance is pretty bad, worse than Hopper.
SynasterBeiter commented on Brood War Korean Translations   blog.sourcedive.net/brood... · Posted by u/todsacerdoti
bee_rider · a year ago
Dumb question from someone who only played money-maps as a kid:

What do the numbers in front of the building mean? 12 Hatcheries seems like… well, 12 seems like a possible but implausible number of hatcheries to build (hypothetically it is possible of course). And 12 spawning pools is obviously not useful. So that makes me think it is the position in the build order list. But, they list other builds, like:

> The second is the 12 Hatch, 12 Pool, 12 Gas

Which doesn’t make a ton of sense in with that parsing. I mean it must not be a straight list. Maybe it is a tree, and 12 is the depth for this building? But that seems late, I can’t think of 11 buildings to build before gas. Maybe they include units too? Or maybe just drones/overlords?

SynasterBeiter · a year ago
It denotes how much supply you should have when you start the building. All of your supply at this stage comes from workers, so it's also an indication how many workers you should train.
SynasterBeiter commented on How Blackjack Works (2007)   blackjackincolor.com/... · Posted by u/Tomte
imglorp · a year ago
Is card counting still possible, or have casinos implemented enough countermeasures to defeat its advantage?
SynasterBeiter · a year ago
Sort of. Look up StevenBridges on YouTube, he documents his career as a card counter. It's certainly possible and you can get some profit, but the casino will sooner or later ban you from blackjack, so you also need a steady supply of them.
SynasterBeiter commented on Get me out of data hell   ludic.mataroa.blog/blog/g... · Posted by u/pavel_lishin
SynasterBeiter · a year ago
I hate whining like these. Just do your job and get over it. No need to be theatrical about it.
SynasterBeiter commented on Project Euler #912: Where are the Odds?   projecteuler.net/problem=... · Posted by u/fzliu
jiggawatts · a year ago
Something I'd love to see is "AoC hard mode": the exact same problems but the input data set is ~10 GB, and/or similarly "scaled" such that naive solutions fail outright.

Other scaling-of-inputs could include: Text with line-lengths over 2 GB, numbers above 2^60, data designed such that naive nested-loop solutions (quadratic scaling) take over a year to compute the answer, etc...

Basically, force developers to solve the problem robustly with: streaming, parallelism, efficient algorithms with good big-O properties, correct data type choice (including intermediate accumulator values!), and so forth.

It could be a three-star challenge feature added to the current version. It wouldn't even require large downloads: a Python script or something similar could be used to generate arbitrarily large inputs. (Alternatively, a common CDN-cacheable prefix with a distinct suffix per competitor.)

SynasterBeiter · a year ago
There are a couple posters on 4chan's /g/ threads on AoC that create "Big Boy" inputs, which is what you're looking for. It's unofficial, though.

Dead Comment

SynasterBeiter commented on Show HN: I made a puzzle game with Three.js   thomasfriday.com/cuboid/... · Posted by u/thomasfriday
SynasterBeiter · 3 years ago
That was pleasant. Thanks!
SynasterBeiter commented on Sugihara's Dog   twitter.com/AkiyoshiKitao... · Posted by u/sohkamyung
paulette449 · 3 years ago
SynasterBeiter · 3 years ago
This guy took inspiration from him and is 3D printing more variations on these illusions.

https://www.youtube.com/watch?v=22x4aALI0VE

SynasterBeiter commented on Apple announces Self Service Repair   apple.com/newsroom/2021/1... · Posted by u/todsacerdoti
ilaksh · 4 years ago
Wait for the next video from Louis. He will expose this as a scam. Yes, they are scared and trying to appease their customers. No, it is NOT in any way actual right-to-repair. They will not let you replace a charge port (for example) and the prices they are asking for parts are ludicrous.
SynasterBeiter · 4 years ago
Is there a price list somewhere? Bear in mind Louis has an incentive here, as this Apple program directly competes with his business.

u/SynasterBeiter

KarmaCake day89September 13, 2019View Original