[java] What is the difference between x86 and x64

What is the difference between x86 and x64 binaries here, we would like to download binaries for Windows 7, Ubuntu 12.04 (32 bit options)

x86 is a 32 bit instruction set, x86_64 is a 64 bit instruction set... the difference is simple architecture. in case of windows os you better use the x86/32bit version for compatibility issues. in case of Linux you will not be able to use a 64 bit s/w if the os does not have the long mode flag.

Whatever I recommend if you have a windows 7 32 bit OS then go for 32bit or x86 binaries and as for Ubuntu 12.04 use command uname -a or grep lm /proc/cpuinfo (grep lm /proc/cpuinfo does not return value for 32 bit as 32 bit os does not has the cpuinfo flag) to know the architecture OS your OS then use the binaries according to your OS.

** Note. Remember you can always install 64 bit os in 32 bit system as long as it supports enhanced 64 bit.. 64 bit os works better some times for multi purpose work and also supports more ram than 32bits. also you can install 32bit s/w in 64 bit os..

** OS = Operating system.

When it comes to memory usage, x86 is limited to circa 3 / 3,5 Gb, while x64 works fine with 4 Gb and more.

Moreover, when it comes to Windows, x86 will run on both X86 and x64 processors, while x64 requires x64 processor only.

Oddly enough it was an Intel thing not a Microsoft thing. X86 referred to the Intel CPU series from the 8086 to the 80486. The Pentium series still use the same addressing system. The x64 refers to the I64 addressing system that Intel came out with later for the 64-bit CPUs. So Windows was just following Intel's architecture naming.

The difference is that Java binaries compiled as x86 (32-bit) or x64 (64-bit) applications respectively.

On a 64-bit Windows you can use either version, since x86 will run in WOW64 mode. On a 32-bit Windows you should use only x86 obviously.

For a Linux you should select appropriate type x86 for 32-bit OS, and x64 for 64-bit OS.

x64 is a generic name for the 64-bit extensions to Intel's and AMD's 32-bit x86 instruction set architecture (ISA). AMD introduced the first version of x64, initially called x86-64 and later renamed AMD64. Intel named their implementation IA-32e and then EMT64.

"When programming with C# you don’t usually need to worry about the underlying target platform. There are however a few cases when the Application and OS architecture can affect program logic, change functionality and cause unexpected exceptions."

"It is common misconception that selecting a specific target will result in the compiler generating platform specific code. This is not the case and instead it simply sets a flag in the assembly’s CLR header. This information can be easily extracted, and modified, using Microsoft’s CoreFlags tool"

https://medium.com/@trapdoorlabs/c-target-platforms-x64-vs-x86-vs-anycpu-5f0c3be6c9e2

If you download Java Development Kit(JDK) then there is a difference as it contains native libraries which differ for different architectures:

• x86 is for 32-bit OS
• x64 is for 64-bit OS

In addition you can use 32-bit JDK(x86) on 64-bit OS. But you can not use 64-bit JDK on 32-bit OS.

At the same time you can run compiled Java classes on any JVM. It does not matter whether it 32 or 64-bit.

x86 is a family of backward-compatible instruction set architectures based on the Intel 8086 CPU and its Intel 8088 variant.

An instruction set architecture (ISA) is an abstract model of a computer. It is also referred to as architecture or computer architecture.

A realization of an ISA is called an implementation. An ISA permits multiple implementations that may vary in performance, physical size, and monetary cost (among other things); because the ISA serves as the interface between software and hardware.

Software that has been written for an ISA can run on different implementations of the same ISA (Exp: 32bit or 64bit). This has enabled binary compatibility between different generations of computers to be easily achieved, and the development of computer families.

Both of these developments have helped to lower the cost of computers and to increase their applicability. For these reasons, the ISA is one of the most important abstractions in computing today.