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Is it better to use std::memcpy() or std::copy() in terms to performance?
...ll have a slight, almost imperceptible performance loss. I just did a test and found that to be untrue: I did notice a performance difference. However, the winner was std::copy.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and ...
What is the meaning of the term arena in relation to memory?
... arena , but never defines it. I've searched for the meaning of the word and how it relates to memory, and found nothing. Here are a few contexts in which the author uses the term:
...
Why aren't variable-length arrays part of the C++ standard?
... space available, isn't good. The argument is, if you know the size beforehand, you can use a static array. And if you don't know the size beforehand, you will write unsafe code.
C99 VLAs could provide a small benefit of being able to create small arrays without wasting space or calling constructo...
javac is not recognized as an internal or external command, operable program or batch file [closed]
...emove old Java paths.
Add the new Java path to PATH.
Edit JAVA_HOME.
Close and re-open console/IDE.
Welcome!
You have encountered one of the most notorious technical issues facing Java beginners: the 'xyz' is not recognized as an internal or external command... error message.
In a nutshell, yo...
Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
.... Then we iterate through for i up to n, doing two things: pressing A once and pressing select all + copy followed by paste j times (actually j-i-1 below; note the trick here: the contents are still in the clipboard, so we can paste it multiple times without copying each time). We only have to consi...
Constant Amortized Time
...erations". Amortised time doesn't have to be constant; you can have linear and logarithmic amortised time or whatever else.
Let's take mats' example of a dynamic array, to which you repeatedly add new items. Normally adding an item takes constant time (that is, O(1)). But each time the array is ful...
Using ThreadPool.QueueUserWorkItem in ASP.NET in a high traffic scenario
...read at all.
That goes for both free threads, created by new Thread(...), and worker threads in the ThreadPool that respond to QueueUserWorkItem requests.
Yes, it's true, you can starve the ThreadPool in an ASP.NET process by queuing too many work items. It will prevent ASP.NET from processing fu...
How do I style a dropdown with only CSS?
...s very good browser support (caniuse) - except for Internet Explorer 11 (and later) and Firefox 34 (and later).
We can improve this technique and add support for Internet Explorer 10 and Internet Explorer 11 by adding
select::-ms-expand {
display: none; /* Hide the default arrow in Interne...
How do I daemonize an arbitrary script in unix?
I'd like a daemonizer that can turn an arbitrary, generic script or command into a daemon .
12 Answers
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When should one use a spinlock instead of mutex?
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The Theory
In theory, when a thread tries to lock a mutex and it does not succeed, because the mutex is already locked, it will go to sleep, immediately allowing another thread to run. It will continue to sleep until being woken up, which will be the case once the mutex is being unl...