CPU Governor Frequency Adjustment via Load Error Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power management techniques for mobile devices fail to adjust CPU operating parameters effectively based on the difference between actual and target CPU loads, leading to inefficient CPU operation and higher energy consumption due to prolonged use of higher-than-necessary frequencies.
Innovation Solution
A computer-implemented method and device that dynamically adjust the CPU operating frequency based on the difference between the target and current CPU loads, using feedback controllers and predictors to ensure the CPU operates at optimal frequencies, minimizing energy waste by switching to lower frequencies sooner and adjusting target loads to match actual usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If CPU operating parameters are adjusted without considering the difference between actual and target CPU loads, then power consumption is reduced, but CPU operation efficiency deteriorates due to prolonged use of higher-than-necessary frequencies
Solution Approach 1:
The patent implements a feedback mechanism that continuously monitors the actual CPU load and compares it with the target CPU load. The difference (error) between these values is fed back to the governor, which then adjusts the CPU frequency accordingly. This closed-loop control ensures that the CPU operates at the most energy-efficient frequency while maintaining the required performance level, resolving the contradiction between energy savings and operational efficiency.
Solution Approach 2:
The patent dynamically adjusts the CPU operating frequency based on real-time load conditions rather than using static frequency settings. The governor continuously adapts the frequency to match the actual CPU load, allowing the system to transition smoothly between different operating states. This dynamic approach enables the CPU to operate at lower frequencies when load is low (saving energy) while maintaining high frequencies when load is high (maintaining efficiency).
2Reliability
If CPU frequency is maintained at higher levels for longer duration to ensure performance, then CPU performance is preserved, but energy consumption increases unnecessarily
Solution Approach 1:
The feedback controller continuously monitors whether the actual CPU load matches the target load and adjusts the frequency accordingly. This ensures that the CPU maintains the minimum necessary frequency to handle the actual load without unnecessarily staying at higher frequencies, thus preserving performance consistency while reducing energy consumption.
Solution Approach 2:
The patent changes the CPU frequency parameter dynamically based on the difference between target and actual loads. By adjusting this critical parameter in real-time, the system can maintain performance reliability when needed while transitioning to lower energy-consuming states when the actual load is below the target, thereby resolving the contradiction between performance consistency and energy usage.
3Loss of energy
If CPU operating parameters are adjusted frequently to match target load, then energy efficiency is improved, but system stability deteriorates due to excessive parameter changes
Solution Approach 1:
The patent applies partial action by adjusting the CPU frequency only when the difference between actual and target loads exceeds a certain threshold. This prevents unnecessary frequency changes when the load is already close to the target, thereby maintaining system stability while still achieving energy savings when significant adjustments are needed. The threshold acts as a filter that prevents excessive parameter changes.
Data Source
AI summary
Adjusting an operating frequency of a CPU includes setting the operating frequency for a current operating cycle based on a CPU load in a prior operating cycle and a target CPU load. A current CPU load associated with the current processing cycle is detected. The CPU operating frequency is adjusted to a new operating frequency based on a difference between the target CPU load and the current CPU load. The operating frequency is adjusted based on minimizing the difference between the target CPU load and the detected load. A CPU load error is determined based on the current CPU load and the target CPU load. The target CPU load is adjusted based on the determined CPU load error and a threshold load error. A prediction is generated on whether to perform a new adjustment of the operating frequency of the CPU prior to expiration of a threshold time duration.