大约有 37,000 项符合查询结果(耗时:0.0342秒) [XML]

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Check synchronously if file/directory exists in Node.js

...nchronous calls. Calls into the I/O subsystem take significant time from a CPU's point of view. Note how easy it is to call lstat rather than lstatSync: // Is it a directory? lstat('/the/path', function(err, stats) { if (!err && stats.isDirectory()) { // Yes it is } }); Bu...
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Fastest sort of fixed length 6 int array

... are single cycle instructions like add/subtract), but for a normal scalar CPU your method looks better. – Paul R May 8 '10 at 16:13 2 ...
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Why is f(i = -1, i = -1) undefined behavior?

...signment cannot be interleaved. It might be optimal to do so, depending on CPU architecture. The referenced page states this: If A is not sequenced before B and B is not sequenced before A, then two possibilities exist: evaluations of A and B are unsequenced: they may be performed in ...
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Measure time in Linux - time vs clock vs getrusage vs clock_gettime vs gettimeofday vs timespec_get?

...e. It is present in C89 and later. At one time this was supposed to be the CPU time in cycles, but modern standards like POSIX require CLOCKS_PER_SEC to be 1000000, giving a maximum possible precision of 1 µs. The precision on my system is indeed 1 µs. This clock wraps around once it tops out (th...
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Why are elementwise additions much faster in separate loops than in a combined loop?

... OK, the right answer definitely has to do something with the CPU cache. But to use the cache argument can be quite difficult, especially without data. There are many answers, that led to a lot of discussion, but let's face it: Cache issues can be very complex and are not one dimension...
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Why aren't programs written in Assembly more often? [closed]

...ur old code can easily make use of the new instructions. What if the next CPU has twice as many registers? The converse of this question would be: What functionality do compilers provide? I doubt you can/want to/should optimize your ASM better than gcc -O3 can. ...
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Custom CSS Scrollbar for Firefox

...and has loads of parameters you can tweak, but it ended up being a bit too CPU intensive for me (and it adds a fair amount to the DOM). Now I'm giving Perfect Scrollbar a go. It's simple and lightweight (6KB) and it's doing a decent job so far. It's not CPU intensive at all (as far as I can tell) a...
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What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?

...han 32-bit? I always thought if there's less bits, there will be less bits CPU has to work on, thus faster. What am I missing here? – Shane Hsu Sep 3 '13 at 11:24 12 ...
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Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?

... relevant, hardly anyone would run raytracing in a scripting language on a CPU these days. I did find pybenchmarks.org – smci Apr 23 '17 at 1:15 ...
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Why are only a few video games written in Java? [closed]

... best with: The biggest problem is that Java is really slow. On a pure cpu / memory / display / communications level, most modern cell phones should be considerably better gaming platforms than a Game Boy Advanced. With Java, on most phones you are left with about the CPU power of an original 4....