Let's say I'm programming in Java or Python or C++ for a simple problem, could be to build an TCP/UDP echo server or computation of factorial. Do I've to bother about the architecture details, i.e., if it is 32 or 64-bit?
IMHO, unless I'm programming something to do with fairly low-level stuff then I don't have to bother if its 32 or 64 bit. Where am I going wrong? Or am I correct???
Knowing how things work, be it how the virtual machine works, and how it works on your platform, or how certain C++ constructs are transformed into assembly will always make you a better programmer, because you will understand why things should be done the way they are.
You need to understand things like memory to know what cache-misses are and why those might affect your program. You should know how certain things are implemented, even though you might only use an interface or high-level way to get to it, knowing how it works will make sure you're doing it in the best way.
For packet work, you need to understand how data is stored on platforms and how sending that across the network to a different platform might change how the data is read (endian-ness).
Your compiler will make best use of the platform you're compiling on, so as long as you stick to standards and code well, you can ignore most things and assume the compiler will whip out what's best.
So in short, no. You don't need to know the low level stuff, but it never hurts to know.
Would one have to know the machine architecture to write code?