Array.Copy vs Buffer.BlockCopy

http://stackoverflow.com/questions/1389821/array-copy-vs-buffer-blockcopy

Since the parameters to Buffer.BlockCopy are byte-based rather than index-based,

you're more likely to screw up your code than if you use Array.Copy,

so I would only use Buffer.BlockCopy in a performance-critical section of my code.

 

http://stackoverflow.com/questions/5099604/any-faster-way-of-copying-arrays-in-c

Use Buffer.BlockCopy. Its entire purpose is to perform fast (see Buffer):

This class provides better performance for manipulating primitive types than similar methods in the System.Array class.

Admittedly, I haven't done any benchmarks标准检查程序, but that's the documentation.

It also works on multidimensional多维 arrays;

just make sure that you're always specifying how many bytes to copy, not how many elements, and also that you're working on a primitive array.

 

Also, I have not tested this, but you might be able to squeeze a bit more performance out of the system if you bind a delegate to System.Buffer.memcpyimpl and call that directly. The signature is:

internal static unsafe void memcpyimpl(byte* src, byte* dest, int len)

It does require pointers, but I believe it's optimized for the highest speed possible, and so I don't think there's any way to get faster than that, even if you had assembly at hand.

 

作者:Chuck Lu    GitHub