Standard Android battery savers only scratch the surface by restricting background data and lowering screen brightness. XtremeBS (Xtreme Battery Saver), developed by DethByte64, takes power efficiency to the absolute extreme. Operating systemlessly at the kernel and framework levels, it grants advanced users unparalleled, dynamic control over CPU core states, Wi-Fi radios, Google Mobile Services (GMS), and Android's deep Doze mechanics. With proper tuning, XtremeBS can significantly multiply your device's standby time and screen-on longevity.
Aggressive Power Optimization
Explore the sophisticated event-driven architecture that allows XtremeBS to drastically cut down power consumption.
Dynamic CPU Control
Forces CPU governors into powersave mode or completely disables specific high-performance cores (e.g., cpu4–cpu7) dynamically when the screen is off or the battery hits critical levels.
Event-Driven Architecture (v2)
Moves away from static constraints. You can configure entirely separate power profiles triggered by OS events such as boot, screen_off, charging, and low_power.
Instant Doze & GMS Management
Bypasses Android's delayed standby timers by forcing the device into Deep or Light Doze immediately upon screen lock. It also features logic to reprioritize (nice), suspend, or kill Google Mobile Services (GMS) wakelocks.
Local Web UI Configuration
No need to edit text files manually. Version 2 integrates a sleek, locally-hosted Web UI running at 127.0.0.1:8081, allowing you to intuitively adjust your allowlists, denylists, and core behaviors.
Technical Breakdown: How XtremeBS Saves Battery
Modern Android processors operate on a "big.LITTLE" architecture, combining low-power efficiency cores with high-power performance cores. When an application runs a background task while your screen is off, the OS may unnecessarily wake up the performance cores, draining significant battery capacity (often referred to as idle drain).
XtremeBS intercepts these states using background daemons. By tracking kernel and OS broadcast events (like android.intent.action.SCREEN_OFF), the module can forcefully execute echo 0 > /sys/devices/system/cpu/cpuX/online to completely shut off the power-hungry cores. Simultaneously, it pushes the device straight into Deep Doze using native dumpsys deviceidle commands, preventing background applications from establishing network connections or running sync tasks until the device screen is turned back on or a charging event is triggered.
While the Web UI is recommended, power users can control the entire framework directly from a terminal emulator (like Termux) using the dedicated XBSctl command suite. If you apply a configuration that is too aggressive—resulting in system freezes or severe lag—you can instantly disable the tweaks by running safe mode via ADB:
adb shell su -c XBSctl safe
Other useful diagnostic commands include:
su -c XBSctl reload- Restarts the daemon and applies new config changes.su -c XBSctl start- Manually forces themanualevent block.
Frequently Asked Questions
screen_off, charging, or low_power. For example, you can program the module to completely disable specific high-performance CPU cores or kill Google Mobile Services (GMS) only when the screen turns off.
adb shell XBSctl safe to instantly enter safe mode and revert the aggressive parameters.
http://127.0.0.1:8081 on your device, which can be launched via the XBSctl command or through your root manager's action button. This interface allows you to configure your event profiles without manually editing text files.
handle_apps=suspend function, you must ensure that your critical applications (such as your keyboard, dialer, launcher, and terminal emulator) are placed in the allowlist. Failure to do so will result in these applications freezing when the screen turns off, rendering the device temporarily unusable until a reboot or safe mode activation is performed.