大约有 15,000 项符合查询结果(耗时:0.0414秒) [XML]

https://stackoverflow.com/ques... 

How does the new automatic reference counting mechanism work?

...ually decide to look at everything it can find starting from the stack and CPU registers. It will never find A,B1,B2,B3 so it will finalize them and recycle the memory into other objects. When you use ARC or MRC, and finish with A it have a refcount of 3 (B1, B2, and B3 all reference it), and B1/...
https://stackoverflow.com/ques... 

Is inline assembly language slower than native C++ code?

...ion scheduling, for example, is very hard to tune by hand) and modern CISC CPUs have very long pipelines too. For some complex microcontrollers even system libraries are written in C instead of assembly because their compilers produce a better (and easy to maintain) final code. Compilers sometimes...
https://stackoverflow.com/ques... 

How to 'bulk update' with Django?

...10's to 100's. The size of the batch that is right for you depends on your CPU and query complexity. This tool is more like a wheel barrow than a dump truck. share | improve this answer | ...
https://stackoverflow.com/ques... 

C# Thread safe fast(est) counter

...d" to (x64). This "bus lock" statement locks the bus to prevent another CPU from accessing the bus while the calling CPU does its operation. Now, take a look at the C# lock() statement's IL. Here you will see calls to Monitor in order to begin or end a section. In other words, .Net lock() stat...
https://stackoverflow.com/ques... 

Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]

...constant folding, transformation of a switch statement into binary search, etc. Thus the benefits to be gained by allowing the compiler to optimize data structures appear to be less tangible than traditional compiler optimizations. ...
https://stackoverflow.com/ques... 

What are Transient and Volatile Modifiers?

...le variable will be read from the computer's main memory, and not from the CPU cache, and that every write to a volatile variable will be written to main memory, and not just to the CPU cache. 2) transient keyword cannot be used along with static keyword but volatile can be used along with static. ...
https://stackoverflow.com/ques... 

What do people find difficult about C pointers? [closed]

...ng a bit too deep in their answers. An understanding of scheduling, actual CPU operations, or assembly-level memory management isn't really required. When I was teaching, I found the following holes in students' understanding to be the most common source of problems: Heap vs Stack storage. It is ...
https://stackoverflow.com/ques... 

Progress indicator during pandas operations

... a new `tqdm` instance with `pandas` # (can use tqdm_gui, optional kwargs, etc.) tqdm.pandas() # Now you can use `progress_apply` instead of `apply` df.groupby(0).progress_apply(lambda x: x**2) In case you're interested in how this works (and how to modify it for your own callbacks), see the examp...
https://stackoverflow.com/ques... 

Cosmic Rays: what is the probability they will affect a program?

... Makers go to huge lengths to make sure the silicon, solder, encapsulation etc doesn't contain any alpha or beta emitters. – Martin Beckett Apr 6 '10 at 3:12 16 ...
https://stackoverflow.com/ques... 

Formula to determine brightness of RGB color

...the only CORRECT algorithm for converting sRGB images, as used in browsers etc., to grayscale. It is necessary to apply an inverse of the gamma function for the color space before calculating the inner product. Then you apply the gamma function to the reduced value. Failure to incorpor