'What are the differences between .NET in 32 or 64 bit systems?
Imagine a pure .NET application which do not uses COM components nor PInvoke. Does it matters if the target system is 32 or 64 bits?
Solution 1:[1]
If the application is targetting AnyCPU, the runtime behavior will be different, in particular, the memory usage and limitations.
On 64bit, there will not be the same 32bit memory limitations (2GB max memory theoretical, but 1.2-1.6 in practice). However, all object references are twice as large, so 64bit systems will use more memory.
Also, 64bit systems often have extra registers, etc, so sometimes performance can improve slightly. This is platform specific, though.
If the application is targetting x86, it will run under WoW64 and act nearly identically to how it will act in 32bit systems.
Solution 2:[2]
Another way it can matter, apart from those identified by Reed Copsey, is if your "pure" application happens to use the System.IntPtr struct for something, or if it uses unsafe code (which isn't the same thing as P/Invoke) and pointer arithmetic.
Another big one to look out for would be calls to pretty much anything in the System.Runtime.InteropServices.Marshal class. There are all kinds of awesome ways to shoot yourself in the foot in there (extremely useful when you need it, of course).
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | Reed Copsey |
| Solution 2 |