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Count(*) vs Count(1) - SQL Server
..., query store overhead, triggers, etc.). It is maybe a few thousand extra CPU instructions. So, count(1) does a tiny bit less work during compilation (which will usually happen once and the plan is cached across multiple subsequent executions). For execution time, assuming the plans are the same ...
Are there any downsides to passing structs by value in C, rather than passing a pointer?
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Unless your struct is tiny or your CPU has many registers (and Intel CPUs have not), the data ends up on the stack and that is also memory and as fast/slow as any other memory. A pointer on the other hand is always small and just a pointer and the pointer itse...
How to simulate Android killing my process
...if it is in the background and the OS decides it needs the resources (RAM, CPU, etc.). I need to be able to simulate this behaviour during testing so that I can ensure that my application is behaving correctly. I want to be able to do this in an automated way so that I can test if the application be...
OnNotify函数 ON_NOTIFY消息总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...个窗口发的(当然可以用参数进行约定)。
如何解决这个问题？
有几种思路：1.重写ON_MESSAGE宏，增加ID的限制；2.模拟按钮单击消息；3.自定义WM_NOTIFY消息。基于这些思路都不能修改MFC底层的代码。
用调试的方式查看MFC的实现代...
How to measure time taken by a function to execute
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In Chrome, press F12 and select the Profiles tab, then Collect JavaScript CPU Profile.
In Firefox, install/open Firebug, and click on the Profile button.
In IE 9+, press F12, click on Script or Profiler (depending on your version of IE).
Alternatively, on your development machine, you can add i...
Disable Interpolation when Scaling a
...n Webkit based) is forced to allow disabling antialiasing. Antialiasing is cpu-intensive operation and antialiasing 6656 x 4096 px image would be too slow, but fortunately unnecessary in such display.
– Timo Kähkönen
Oct 10 '12 at 15:45
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Formula to determine brightness of RGB color
... if you do it as: Y = (R<<1+R+G<<2+B)>>3 (thats only 3-4 CPU cycles on ARM) but I guess a good compiler will do that optimisation for you.
– rjmunro
Mar 11 '15 at 11:16
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What are important languages to learn to understand different approaches and concepts? [closed]
...oreover, it is also a very universal, C compilers exist for (almost) every CPU architecture ever devised.
– dietr
May 12 '11 at 8:05
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iTextSharp - Sending in-memory pdf in an email attachment
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It's not. It's a waste of memory and CPU time because the bytes have to be copied from one to the other.
– Serguei Fedorov
Jun 4 '15 at 21:09
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How to handle :java.util.concurrent.TimeoutException: android.os.BinderProxy.finalize() timed out af
...ing most User Land processes for a while, and turning Screen off, reducing CPU cycles, etc. The way this is done - is on a Linux system level where the processes are Paused mid run. This can happen at any time during normal Application execution, but it will stop at a Native system call, as the cont...