mattnewport

84 ms·

841.
by mattnewport 12y ago
To answer the first part of your question, a locked xchg is the usual way to implement a sequentially consistent store on x86 without an explicit fence. For sequentially consistent loads, plain mov suffices, providing it synchronizes with a
842.
by mattnewport 12y ago
It's a little while since I looked closely at this and it's easy to get this stuff wrong but here's what I concluded when digging into this in the context of a codebase I was maintaining that made heavy use of lock free techn
843.
by mattnewport 12y ago
Missed this somehow before making my comment saying essentially the same thing. Unfortunately the code base I've been maintaining heavily overuses mfences at a measurable performance penalty on x64.
844.
by mattnewport 12y ago
This article is pretty old and I suspect if you asked Bartosz now he'd explain it slightly differently. You certainly need to use instructions that impose additional ordering guarantees on x86 in these kinds of situations but you don&#
845.
by mattnewport 12y ago
When can we get an IDE that can do this, and track copy / paste across source files :)
846.
by mattnewport 12y ago
We've probably seen a bit of a slow down in Moore's law over the last 10 years, at least when it comes to Intel CPUs but I think you're exaggerating the extent of the slowdown. Some benchmarks are heavily dependent on RAM lat
847.
by mattnewport 12y ago
Did you actually read any of the linked messages in which Linus makes a strong case for why this oft repeated claim about x86 turned out not to be a real problem in practice? If you're going to disagree with what Linus is saying can yo
848.
by mattnewport 12y ago
Current approaches are a bit of a hack. You have multiple stereo camera pairs and to handle intermediate directions you do some software interpolation between them. Despite being a hack it works well enough to be reasonably immersive. The S
849.
by mattnewport 12y ago
At a minimum this can give you a much better and more modular version of precompiled headers. Because modules are guaranteed not to be affected by macros or ordering of module imports in the importing translation units you can get a modular
850.
by mattnewport 12y ago
Why is the idea that alcohol and red meat are harmful so ingrained in society that even years of scientific evidence to the contrary are ignored? For alcohol: http://www.psmag.com/navigation/health-and-behavior/tru
851.
by mattnewport 12y ago
Yes, they did talk about this briefly. I believe Carmack talks about it in his keynote (video linked in another HN news post). Basically the issue in the near to medium term is that VR isn't a big enough market to drive the development
852.
by mattnewport 13y ago
But then, the number of people who don't really understand pointers but who seem to be C/C++ developers is a little surprising...
853.
by mattnewport 13y ago
I kind of expected 'learn on someone else's dime' to be about a company providing training as part of your job rather than a company hiring people with the expectation that they both do the job they are hired for and learn on
854.
by mattnewport 13y ago
I agree, in the games industry we use C++ for a few reasons: * Performance * Portability * Direct API access (D3D, OpenGL, console specific APIs) * Large legacy codebases * Control over memory management Go doesn't really address all t