大约有 15,000 项符合查询结果（耗时：0.0253秒） [XML]
Is MD5 still good enough to uniquely identify files?
...ly identify it given all the breaking of MD5 algorithm and security issues etc? Security is not my primary concern here, but uniquely identifying each file is.
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外媒评本轮科技泡沫：创业公司首当其冲 九成将消失 - 资讯 - 清泛网 - 专注...
...团队，这个团队只能以财报电话会议内容以及各种棘手的问题为依据，对私营公司进行投资——把它们当作是上市公司。
总之，越来越多的日常投资者正暴露给后期私营科技公司，无论结果是好还是坏。据博伊德介绍，作为富...
How do I measure time elapsed in Java? [duplicate]
...in milliseconds. It has methods methods like split(), suspend(), resume(), etc that allow to take measure at different points of the execution and that you may find convenient. Have a look at it.
System.nanoTime()
You may prefer to use System.nanoTime() if you are looking for extremely precise mea...
Finding Number of Cores in Java
...logical threads actually available to the JVM (at startup I guess). Using CPU affinity the user/OS can restrict the number of "cores" a JVM sees. You can even do it on a running JVM but I'm not too sure how this influence availableProcessors().
– SyntaxT3rr0r
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Why does my application spend 24% of its life doing a null check?
...uting instructions, it is accessing memory. The execution core of a modern CPU is many times faster than the memory bus. A problem related to distance, the further an electrical signal has to travel, the harder it gets to get that signal delivered to the other end of the wire without it being corrup...
What is the advantage of GCC's __builtin_expect in if else statements?
...ase precedes the foo case (as opposed to the C code). This can utilise the CPU pipeline better, since a jump thrashes the already fetched instructions.
Before the jump is executed, the instructions below it (the bar case) are pushed to the pipeline. Since the foo case is unlikely, jumping too is un...
“register” keyword in C?
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It tells the compiler to try to use a CPU register, instead of RAM, to store the variable. Registers are in the CPU and much faster to access than RAM. But it's only a suggestion to the compiler, and it may not follow through.
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Select random lines from a file
...0 --file lines_78000000000.txt > /dev/null 0.02s user 0.01s system 80% cpu 0.047 total
The reason it is so fast, well I don't read the whole file and just move the file pointer 10 times and print the line after the pointer.
Gitlab Repo
Old attempt
First I needed a file of 78.000.000.000 lines:...
Why is Magento so slow? [closed]
...ehind the scenes (application configuration, system config, layout config, etc.) that involve building up giant XML trees in memory and then "querying" those same trees for information. This takes both memory (storing the trees) and CPU (parsing the trees). Some of these (especially the layout tre...
Queue.Queue vs. collections.deque
...ation.
In fact the heavy usage of an extra mutex and extra method ._get() etc. method calls in Queue.py is due to backwards compatibility constraints, past over-design and lack of care for providing an efficient solution for this important speed bottleneck issue in inter-thread communication. A lis...