How to find out the Linux bitness

Linux can be 32-bit or 64-bit, depending on the processor architecture. The 32-bit version of Linux can be used on x86 and ARM processors, while the 64-bit version can be used on x64 and ARM64 processors. Currently, most new computers and servers use 64-bit versions of Linux.

What is system bitness?

The bit capacity of a Linux system refers to its ability to process data and is determined by the number of bits in the central processing unit (CPU). Bitness can be 32-bit or 64-bit. A 32-bit system can only process 32-bit data, whereas a 64-bit system can process both 32-bit and 64-bit data. The system's bitness affects its performance, power consumption, memory size and other parameters.

What does it provide?

Linux bitness (32-bit or 64-bit) determines how much data the processor can process per clock cycle, as well as the maximum amount of addressable memory. Here are the main aspects it affects:

1. Addressable memory size: 32-bit systems can address up to 4 GB of RAM (2^32 bytes), while 64-bit systems can handle much larger amounts (theoretically up to 16 EB, in practice up to several terabytes in modern systems).
2. Performance: 64-bit applications can process more data per one clock, which may result in higher performance, especially when working with large amounts of data.
3. Compatibility: some programs may be available only in the 64-bit version, which limits the use of 32-bit systems for new applications.
4. Register usage: 64-bit systems have more processor registers, which can increase the efficiency of program execution.
5. Support of modern technologies: new technologies and functions such as extended instructions and improved security are often available only in 64-bit versions.

The choice of system bitness can have a significant impact on software performance, features, and compatibility.

Why do I need to know the Linux bitness?

Knowing the Linux system bitness is important for understanding and selecting the correct version of software. For example, a program created for a 32-bit system may not work on a 64-bit system and vice versa. In addition, knowing the bit capacity will help you determine the maximum supported RAM and processor, which is essential when selecting and upgrading a computer.

See the bitness in the terminal

The instruction is simple:

1. Open a terminal by pressing the keyboard shortcut Ctrl+Alt+T.
2. Write the command uname -m and press Enter.
3. You will see the answer in the form of your system architecture. If the answer line mentions x86_64, it means you have 64-bit Linux. If the answer line mentions i386, i486, i586, or i686, that means you have 32-bit Linux.
4. You can also use the getconf LONG_BIT command, which will show you the current system bitness. If the output is 32, it means you have 32-bit Linux, if it is 64, it means you have 64-bit Linux.

It's important to remember that in order to use 64-bit Linux, you must also have a processor that is 64-bit.

In Ubuntu, to do this, you need to open the Settings utility and then the about systemsection :

The OS Type section specifies the architecture of the system, which, in this case, is 64-bit. But you should not forget that the presence of 64-bit architecture does not mean that you cannot run 32-bit applications and libraries. Due to the backward compatibility of this architecture, processors are still able to perform tasks intended for a 32-bit system.

To do so, you will need to install the appropriate driver set and the necessary 32-bit libraries. However, backward compatibility does not work the other way around: 32-bit systems cannot run 64-bit applications. Now you have the knowledge to help you determine the bitness of your Linux system.