Overview

spdlog is a lightning-fast C++ logging library designed for performance and flexibility. It offers a rich set of features, including customizable formatting powered by the excellent fmt library, asynchronous logging, multiple output targets, and robust filtering capabilities. Whether you need to log to the console with colors, rotate log files, or integrate with system logging facilities like syslog, spdlog provides an efficient and elegant solution.

Key Features

• Extreme Performance: Engineered for speed, spdlog boasts benchmarks that showcase its ability to handle millions of messages per second in synchronous mode and hundreds of thousands in asynchronous mode.
• Flexible Installation: Choose between a header-only version for simplicity or a compiled version for optimized build times.
• Rich Formatting: Leverage the power of fmt for expressive and efficient string formatting, including support for user-defined types and custom flags.
• Diverse Output Targets (Sinks): Log to the console (with color support), rotating files, daily files, syslog, Windows event log, Windows debugger, and even Qt widgets. Custom sinks are easily extendable.
• Asynchronous Logging: Improve application responsiveness by offloading logging operations to background threads, with configurable queue overflow policies.
• Runtime Level Control: Dynamically adjust log levels via environment variables or command-line arguments, enabling fine-grained control over log verbosity.
• Backtrace Support: Capture debug messages in a ring buffer and dump them on demand, ideal for debugging complex issues.
• Stopwatch Utility: Easily measure code execution times with the integrated spdlog::stopwatch.
• Binary Data Logging: Efficiently log raw binary data in a readable hex format.

Typical Use Cases

spdlog is an ideal choice for a wide range of C++ applications, including:

• High-Performance Applications: Where logging overhead must be minimal, such as game development, real-time systems, and network services.
• Complex Software Systems: For detailed debugging and operational monitoring across various components, with the ability to filter logs by module or severity.
• Cross-Platform Development: Its broad platform support (Linux, Windows, macOS, Android) makes it suitable for applications targeting diverse environments.
• Applications Requiring Dynamic Logging Control: Easily adjust log levels in production without recompilation using environment variables or command-line arguments.
• Embedded Systems: Where resource constraints are a concern, the header-only option and efficient design make it a compelling choice.