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sysctl
Sysctl is a command line tool in Unix-like operating systems that allows users to view, modify, and manage the kernel parameters at runtime. It stands for "system control" and provides a way to adjust various settings related to the system's performance, security, and behavior.
With sysctl, users can examine the current values of kernel parameters, which are stored in a hierarchical structure called the sysctl tree. This tree can be navigated using dot notation, allowing users to access specific parameters or even entire branches of the tree.
Sysctl also enables users to modify these kernel parameters on the fly, providing a dynamic way to adjust system behavior without requiring a reboot. However, it is important to exercise caution while changing these parameters, as incorrect values can adversely affect system stability and performance.
The tool includes options to reload the sysctl configuration file, which ensures changes made to the parameters persist across system reboots. Additionally, sysctl supports the ability to specify different configuration files, allowing users to manage separate modifications for specific purposes or environments.
Sysctl can be particularly useful for system administrators, developers, and power users as it grants granular control over various aspects of the operating system, thereby allowing them to optimize system performance, secure the system, and customize its behavior to meet specific requirements. Overall, sysctl can be a powerful command line tool for managing and fine-tuning Unix-like systems.
List of commands for sysctl:
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sysctl:tldr:2a401 sysctl: Set a changeable kernel state variable.$ sysctl -w ${section-tunable}=${value}try on your machineexplain this command
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sysctl:tldr:725fe sysctl: Show CPU model.$ sysctl -n machdep.cpu.brand_stringtry on your machineexplain this command
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sysctl:tldr:75de0 sysctl: Show available CPU features (MMX, SSE, SSE2, SSE3, AES, etc).$ sysctl -n machdep.cpu.featurestry on your machineexplain this command
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sysctl:tldr:79717 sysctl: Show all available variables and their values.$ sysctl -atry on your machineexplain this command
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sysctl:tldr:b8557 sysctl: Get currently open file handlers.$ sysctl fs.file-nrtry on your machineexplain this command
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sysctl:tldr:c48b2 sysctl: Show Apple model identifier.$ sysctl -n hw.modeltry on your machineexplain this command
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sysctl:tldr:d80b0 sysctl: Get limit for simultaneous open files.$ sysctl fs.file-maxtry on your machineexplain this command
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sysctl:tldr:f75f8 sysctl: Apply changes from `/etc/sysctl.conf`.$ sysctl -ptry on your machineexplain this command