Powersave

Powersave refers to techniques and configurations aimed at reducing the power consumption of electronic devices and computer systems, typically to extend battery life or reduce energy costs. It encompasses both hardware capabilities and software policies and is common in mobile devices, laptops, embedded systems, and data centers.

Common methods include entering low-power states during inactivity (sleep, standby, or hibernate); turning off or disabling unused peripherals; and reducing power use through dynamic voltage and frequency scaling (DVFS), clock gating, and power gating. Software optimization also plays a role, by minimizing background activity and scheduling tasks to avoid unnecessary wakeups.

Power management policies are implemented at firmware, hardware, or operating system levels. In Linux, for example, a powersave CPU governor can set the processor to minimum frequency to save energy. Other platforms offer battery saver or low power modes. These profiles balance energy use against performance and responsiveness and may be triggered automatically by battery level or temperature or set by the user.

Hardware design also contributes to powersave, with energy-efficient components, advanced sleep states, and support for standards such as ACPI in PCs and power-management features in mobile systems. Effective powersave strategies consider wake latency, user experience, and total cost of ownership.

Measuring powersave effectiveness involves power profiling and energy accounting using sensors and tools, with metrics like battery life, energy per operation, and wake-up frequency. The term is often used generically to describe energy-saving behavior rather than a specific product or feature.