GPU Clock Scaling via Idle Time Thresholds

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Graphics processors in computer systems face inefficiencies due to periods of idle time, leading to increased power consumption and reduced battery life in mobile devices, as they continue to process frames faster than the display refresh rate, resulting in unnecessary energy usage.

Innovation Solution

Implementing dynamic clock scaling for graphics processors based on idle time percentages, where the clock rate is reduced if idle time exceeds a high threshold and increased if below a low threshold, with adjustable limits and evaluation periods to optimize energy efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If the graphics processor runs at a high clock rate continuously, then processing speed is improved, but power consumption increases during idle periods

Engineering Contradiction:

Improveprocessing speedVSAvoidpower consumption

Core Design Contradiction:

SpeedVSUse of energy by moving object

Solution Approach 1:

The patent implements dynamic clock rate adjustment by transitioning the graphics processor between multiple clock states (first clock rate during idle periods, second clock rate during active processing). This dynamic adaptation allows the system to optimize power consumption during idle periods while maintaining high processing speed when needed, directly resolving the contradiction between continuous high-speed operation and energy efficiency.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the operational parameter (clock rate) of the graphics processor based on its operational state. By monitoring whether the processor is idle or actively processing and adjusting the clock rate accordingly, the system achieves both low power consumption during idle periods and high processing speed during active periods, eliminating the need to continuously run at maximum clock rate.

Inventive Principle:

Principle #35Parameter changes

2Use of energy by moving object

If the graphics processor reduces clock rate during idle time, then power efficiency is improved, but response time may increase when processing resumes

Engineering Contradiction:

Improvepower efficiencyVSAvoidresponse time

Core Design Contradiction:

Use of energy by moving objectVSLoss of time

Solution Approach 1:

The patent implements a warm state between complete idle and full active processing by using an intermediate clock rate. When the processor transitions from idle to active, it first increases to an intermediate clock rate before reaching full operating speed, allowing preliminary preparation that reduces the overall response time while still maintaining power efficiency during truly idle periods.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system uses periodic evaluation of processor activity and implements staged clock rate transitions rather than abrupt changes. This periodic monitoring and gradual adjustment approach allows the processor to efficiently transition between states, minimizing response time penalties while maintaining power savings during idle periods.

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS9773344B2Graphics processor clock scaling based on idle time

Publication Date: 2017.09.26 NVIDIA CORP

AI summary

A method for graphics processor clock scaling comprises the following steps. A percentage of idle-time is calculated, based upon an elapsed idle-time and an elapsed active time. A graphics processor clock rate is reduced if the percentage of idle time is higher than a high limit threshold. The graphics processor clock rate is increased if the percentage of idle time is lower than a low limit threshold.