Genbox
Joined 15 years ago
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187
Member since
Jul 25
Recent submissions
Comment · 2 months ago
Agner's table[1] for Intel IceLake/TigerLake shows FDIV to have higher latency, but slightly better throughput.
For latency:
- DIV/IDIV r32: 12 cycles
- DIV/IDIV r64: 15 cycles
- FDIV: 14–16 cycles
Throughput:
- DIV/IDIV r32: 6 cycles
- DIV/IDIV r64: 10 cycles
- FDIV: 4–5 cycles
I didn't check for a more recent CPU.
[1] https://www.agner.org/optimize/instruction_tables.pdf page 366 & 369
Comment · 6 months ago
Publishing a zero knowledge proof rather than the solution is pretty clever.
Comment · 7 months ago
If I would like to build a visualization like this, but for a data ingestion pipeline, any tips on where to start?
I have it visually in my head, but it feels overwhelming getting it into a website.
Comment · 8 months ago
PHP loads all available functions into a giant hashset (see zend_disable_function in PHP's source). 'disable_functions' removes the functions from the hashset, making them unavailable to be called. Due to its interpreted nature, this indirection works much like a sandbox would.
Comment · 8 months ago
Are you saying that two weak factors are more secure than one strong factor?
Comment · 9 months ago
That is also a Windows 10 feature
Comment · 10 months ago
I agree with this. As someone who took 3 degrees in computer science, one called "systems developer" and another called "software engineer", I can confidently say we have a taxonomy problem in computer science education.
It makes me crazy that companies labels there entire programmer workforce as "software engineers" when there are no engineering concepts involved at all. Other fields (medical, mechanical, civil engineering) are a lot more mature in this area and have solved this issue long ago.
Comment · 11 months ago
Thanks!
The direct hooking into the narrow phase solver is the most performant way to go about it, but it does present several issues in state management. I did the same thing in Farseer Physics Engine, but also added high level events on bodies[1]. The extra abstraction makes it easier to work with, but due to the nature of delegates in C#, it was also quite a bit slower.
They could do with creating defaults for the narrow phase handler, buffer pool, threat dispatcher, etc. for devs who don't need extreme performance and just want a simple simulation.
[1] https://github.com/Genbox/VelcroPhysics/blob/ddf8292da6bc59e...
Comment · 11 months ago
Wow. That is actually very impressive. Things have moved quite a lot since I did a physics engine.
What makes it difficult to integrate?
Comment · 11 months ago
That's a bit disingenuous. Can you substantiate your claims?
Comment · 11 months ago
The security of the Apple ecosystem is miles ahead of others. Every time I reverse engineer some component of their OS, it is very different from what I've seen before. I always find myself surprised by their thoughtfulness and engineering craft.
Recently I've taken on their code signing component. The concepts they've created, such as identifying applications by their "designated requirements" is a stroke of genius. It makes the system completely stateless and capable of almost anything without auxiliary data structure or additional code.
I've seen other engineering teams try and fail at building something similar, and never with such powerful simplicity.
Comment · 11 months ago
The condition is called Anosmia and can stem from different sensor and brain conditions. It would be interesting to try the technique on people with these conditions to map the different kinds of olfactory failures.
If you get in contact with the researchers, please let us know how it went.
Comment · 1 year ago
It is also kinda a self-burn. Chromium an aging code base [1]. It is written in a memory unsafe language (C++), calls hundreds of outdated & vulnerable libraries [2] and has hundreds of high severity vulnerabilities [3].
People in glass houses shouldn't throw stones.
[1] https://github.com/chromium/chromium/commits/main/?after=c5a...
[2] https://github.com/chromium/chromium/blob/main/DEPS
[3] https://www.cvedetails.com/product/15031/Google-Chrome.html?...
Comment · 1 year ago
This is related to a technical deep dive released a few weeks ago: https://github.com/Zephkek/Asus-ROG-Aml-Deep-Dive?tab=readme...
Comment · 1 year ago
I generally agree. However, there are several important optimizations that Roslyn does not yet have. I love the improvements in newer versions of the compiler as much as the next guy, but historically, waiting 20 years on getting basic inlining, hoisting and SIMD accelerations has left many of us with the only option of not relying on C# for performance.
I built Farseer Physics Engine 3.0, SimpleS3 and about 25 other open source projects. Check them out over at https://github.com/genbox
I am also the founder and director of Chronos, a platform for investigating large-scale security incidents using forensics techniques.