lscpu

What is lscpu?

lscpu (list CPU architecture) is a simple yet powerful command-line utility that displays a wealth of information about your system’s central processing unit (CPU). This information goes beyond basic specifications, providing details for performance analysis, troubleshooting, and software compatibility.

Key Information Provided by lscpu

The output of lscpu typically includes, but isn’t limited to:

• Architecture: The underlying CPU architecture (e.g., x86_64, ARM).
• CPU op-mode(s): The operating modes supported by the CPU (e.g., 32-bit, 64-bit).
• Byte Order: The endianness of the system (big-endian or little-endian).
• CPU(s): The total number of CPU cores.
• On-line CPU(s) list: A list of currently active CPU cores.
• Thread(s) per core: The number of hardware threads per core (hyperthreading).
• Core(s) per socket: The number of cores per physical CPU socket.
• Socket(s): The number of physical CPU sockets.
• NUMA node(s): Information about Non-Uniform Memory Access architecture, if applicable.
• Vendor ID: The manufacturer of the CPU (e.g., GenuineIntel, AuthenticAMD).
• CPU family: A numerical identifier for the CPU family.
• Model: A numerical identifier for the specific CPU model.
• Model name: The descriptive name of the CPU model (e.g., Intel Core i7-10700K).
• Stepping: A revision number indicating manufacturing refinements.
• CPU MHz: The current CPU clock speed.
• BogoMIPS: A very rough estimate of CPU performance (generally unreliable for comparisons).
• Flags: A detailed list of CPU features and instruction set extensions (e.g., SSE, AVX, AES).
• Cache: Information about different levels of CPU cache (L1, L2, L3).

Using lscpu: Code Examples

Let’s look at lscpu with practical examples:

1. Basic lscpu Output:

The simplest usage is just typing the command:

lscpu

This will display an overview of your CPU information in a structured format.

2. Filtering Output with grep:

You can use grep to filter the output and extract specific details. For example, to find the CPU model name:

lscpu | grep "Model name"

To find all flags that contain “AVX”:

lscpu | grep -i "avx"

3. Getting Specific Information:

lscpu also allows you to extract specific fields using the --parse=VALUE option. For example, to get only the CPU architecture:

lscpu --parse=architecture

4. Detailed Cache Information:

To get a detailed breakdown of cache information:

lscpu --extended | grep Cache

This uses the --extended flag for a more verbose output focused on cache details. Note that the output might vary depending on your CPU.

5. Focusing on specific aspects

For instance, focusing solely on the number of cores and threads:

lscpu | grep -E "(CPU\(s\)|Thread\(s\))"

These examples demonstrate the versatility of lscpu and its ability to provide tailored information based on your needs. The command’s simplicity and effectiveness make it a tool for any Linux user.