dev_helpers.sh

This repository contains a collection of shell functions and aliases designed to help you quickly and consistently prepare your Linux system for performance profiling, debugging, and low-level system configuration. It gives you control over various CPU and memory settings, such as disabling SMT (hyper-threading), enabling/disabling frequency scaling, managing RDPMC access, and much more.

Note: This script is meant to be sourced into a shell session, not executed directly. It enables quick and consistent adjustments of system settings.

Features ✨

Tracing and Debugging 🔍

• Enables access to performance monitoring counters (RDPMC).
• Allows ptrace, kptr, and perf events for system tracing.

CPU Management ⚡

• Disable or enable hyper-threading (SMT).
• Disable efficiency cores (E-cores) to optimize power/thermal efficiency.
• Switch to single-core mode (only CPU0 active).
• Restore all CPU cores.

Security and Memory Management 🔐

• Disable Address Space Layout Randomization (ASLR) for debugging.
• Manage kernel parameters related to performance monitoring.

Convenient Aliases 💡

• Set up easy-to-use aliases for workflows like enabling VTune-like settings or restoring default configurations.

Setup 🛠️

Follow these steps to get started:

1. Clone the repository:

   git clone https://github.com/Saket-Upadhyay/systems-dev-helpers.git

2. Source the script in your shell configuration: Add this line to your .bashrc, .zshrc, or the appropriate shell configuration file:

   source /path/to/dev_helpers.sh

   use QUIET_LOAD to disable init banner:

   QUIET_LOAD=1 source /path/to/dev_helpers.sh

3. Reload the shell configuration:

   • For Bash:

     source ~/.bashrc

   • For Zsh:

     source ~/.zshrc

Usage 🚀

Once the script is sourced, you’ll have access to a variety of functions and aliases for system tuning:

Core Functions ⚙️

• enable_tracing_privileges: Grants access to kernel-level tracing and debugging tools (e.g., perf, ptrace).
• disable_aslr: Disables Address Space Layout Randomization (ASLR) for debugging.
• undo_debug_privileges: Restores kernel settings to their default secure configurations.
• disable_e_cores: Disables efficiency cores on multi-core systems to optimize performance.
• restore_all_cores: Re-enables all CPU cores.
• switch_to_single_core_mode: Switches to single-core mode (only CPU0 active).
• disable_smt / enable_smt: Disables or enables hyper-threading (SMT).
• disable_frequency_scaling: Forces CPU governors to "performance" mode, disabling dynamic frequency scaling.
• enable_frequency_scaling: Restores the default frequency scaling behavior.

Aliases 🖥️

• vtune_mode: Set up the system for performance profiling with tracing enabled, SMT disabled, and frequency scaling disabled.
• debug_off: Restores all kernel settings to secure default values.
• single_core_mode: Switches to single-core mode (only CPU0).
• restore_cores: Re-enables all CPU cores.

Example Usage 📚

1. Enable VTune-like profiling mode:

   vtune_mode

   

2. Disable SMT and switch to single-core mode:

   single_core_mode

3. Restore all settings:

   debug_off

   

⚠️Direct Execution: This script is designed to be sourced, not executed directly. If you try to run it as a standalone script, it will result in an error and exit immediately.

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Requirements

• Linux-based operating system
• sudo privileges for most operations
• A Bash or Zsh shell environment

Future Plans and Contributing 🤝

This script was originally developed as part of my memory tracing and performance analysis research. As such, some of the default configurations and tuning profiles are designed specifically for those use cases.

The broader goal moving forward is to evolve the script into a modular and extensible toolkit for a wide range of system profiling, debugging, and benchmarking scenarios—enabling quick setup across diverse environments.

Contributing

Contributions are highly encouraged. You are welcome to:

• Add new functions or profiles tailored to different performance tuning use cases
• Improve compatibility across distributions or kernel versions
• Refactor existing code for clarity or maintainability
• Report issues or suggest enhancements via GitHub Issues

To contribute:

1. Fork the repository
2. Create a feature branch
3. Make your changes and follow the existing coding style
4. Submit a pull request for review

Please ensure that all contributions maintain consistency with the script’s existing structure and are clearly documented.

License 📄

This project is licensed under the MIT License - see the LICENSE file for details.

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