Google is introducing a new optimisation technique to improve the Android kernel, a change that could make Android phones faster and more efficient. It is called Automatic Feedback-Directed Optimisation (AutoFDO). This update aims to deliver faster app launches, a smoother user experience and better battery efficiency for smartphones. Google’s Android LLVM toolchain team shared the details that outline how AutoFDO is expected to enhance Android’s performance.
The Android kernel acts as the bridge between a device’s hardware, processor and applications that are running on a device. According to Google, it manages approximately 40 per cent of a phone’s CPU time so, even a small improvement to the kernel can lead to a noticeable gain in the device’s performance. Google’s new approach relies on data collected from controlled lab tests that simulate real-world usage patterns using popular Android apps.
During these tests, profiling tools track which parts of the kernel are used most frequently, often referred to as “hot” code paths. AutoFDO then uses this information to guide the compiler when rebuilding the kernel, allowing it to organise code more efficiently around the operations that are used most often.
Traditional kernel compilation typically relies on general assumptions about how software will be used. AutoFDO changes this by using real-world usage data to identify the most frequently used code paths — often referred to as “hot” paths — and optimising them first. This allows the compiler to make smarter decisions when rebuilding the kernel, enabling heavily used parts of the system to run more efficiently.
In early internal testing, Google reported a 2.1 per cent faster boot time and a 4.3 per cent improvement in cold app launch times, along with gains across several other performance metrics. The optimisation runs in a “conservative by default” mode, meaning it can fall back to traditional compilation methods if a situation falls outside the patterns identified during testing.
AutoFDO is being rolled out to the latest Android kernel branches, including android16-6.12 and android15-6.6, with plans to support future versions such as android17-6.18. By applying optimisation to the kernel itself, Google expects Android devices to deliver faster app launches, smoother multitasking, and overall, more responsive performance.
