Sigar

Sigar, short for System Information Gatherer And Reporter, is a cross-platform software library designed to retrieve low-level system information in a uniform way across different operating systems. It originated with Hyperic, a company focused on IT monitoring, to support its management products. After Hyperic was acquired by VMware in 2009, SIGAR moved into the realm of open-source, community-maintained tooling and became a reference point for portable system metrics.

The library provides a stable API to access a range of metrics, including CPU usage and topology, memory and swap, file systems and disks, network interfaces and throughput, and information about processes and system sensors. SIGAR is implemented in native code (primarily C) and offers bindings for several programming languages, notably Java and Python, enabling applications to embed the library and gather data without writing platform-specific code.

Platform support covers major operating systems such as Linux, Windows, macOS, and common Unix variants. Because the metrics are retrieved through native libraries, applications must distribute the appropriate binaries for each target platform. In practice, SIGAR has been used by monitoring and observability tools, as well as by custom dashboards and performance analysis utilities, providing a bridge between platform-specific data sources and cross-platform tooling.

Over time, other libraries with similar goals—such as OSHI for Java or psutil for Python—have gained popularity, but SIGAR remains referenced in legacy integrations and older monitoring solutions.