Processor Error Recovery via State Snapshot and Dynamic Precision Switching

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing processors lack efficient methods to manage and recover from excessive error accumulation during approximate computing, which affects accuracy and power consumption.

Innovation Solution

A processor design that includes a snapshot storage mechanism to record its state before performing approximate computations, with an error indicator to detect when errors exceed a bound, allowing the processor to restore its state and re-perform computations with full accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If approximate computing is used to reduce power consumption, then energy efficiency is improved, but computation accuracy deteriorates

Engineering Contradiction:
Improvepower consumptionVSAvoidcomputation accuracy
Core Design Contradiction:
Use of energy by moving objectVSMeasurement precision

Solution Approach 1:

The processor dynamically switches between approximate computing mode and full accuracy mode based on error accumulation. The error indicator monitors computation accuracy in real-time, and when error exceeds a threshold, the system transitions from approximate mode back to full accuracy mode, creating a dynamic adaptation mechanism that resolves the contradiction between power consumption and accuracy.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the computation precision parameter based on error accumulation. Initially, computations are performed with reduced precision (approximate mode) to save power. When the error indicator detects that accumulated error exceeds a threshold, the precision parameter is changed back to full accuracy, allowing the system to optimize power consumption while maintaining accuracy when necessary.

Inventive Principle:
Principle #35Parameter changes

2Use of energy by moving object

If approximate computing is performed without error recovery, then power consumption is reduced, but reliability deteriorates

Engineering Contradiction:
Improvepower consumptionVSAvoidcomputation reliability
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The processor takes a snapshot of its state before performing approximate computations. This preliminary action prepares the system for potential error recovery by preserving the pre-computation state, enabling reliable recovery if approximate computing produces excessive error, thus maintaining reliability while allowing power-efficient approximate mode operation.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The error indicator provides continuous feedback on the accumulated error during approximate computing. When the error exceeds a threshold, this feedback triggers the recovery mechanism that restores the processor state from the snapshot and re-performs computations in full accuracy mode, ensuring reliability while maintaining power efficiency benefits.

Inventive Principle:
Principle #23Feedback

3Measurement precision

If full accuracy computing is always used, then computation accuracy is maintained, but power consumption increases

Engineering Contradiction:
Improvecomputation accuracyVSAvoidpower consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

Instead of always performing full accuracy computing, the system applies partial action by using approximate computing for computations where full accuracy is not critical. The error indicator monitors when accuracy becomes important, and only then does the system switch to full accuracy mode, avoiding the excessive power consumption of always using full precision while maintaining accuracy when necessary.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP2908242B1Processor that recovers from excessive approximate computing error
Publication Date: 2019.07.17 VIA ALLIANCE SEMICON CO LTD
  • EP2908242B1 patent drawingFigure 1
  • EP2908242B1 patent drawingFigure 2
  • EP2908242B1 patent drawingFigure 3

AI summary

A processor includes a storage configured to receive a snapshot of a state of the processor prior to performing a set of computations in an approximating manner. The processor also includes an indicator that indicates an amount of error accumulated while the set of computations is performed in the approximating manner. When the processor detects that the amount of error accumulated has exceeded an error bound, the processor is configured to restore the state of the processor to the snapshot from the storage.