Dynamic Foreground Scan Control for NAND Memory Integrity

Solution Overview

Problem

Conventional memory systems face challenges in optimizing the tradeoff between host operation performance and data integrity when performing foreground and background media scans in NAND-type memory devices.

Innovation Solution

The method involves dynamically enabling and disabling foreground scans of blocks in a memory device, using a schedule that prioritizes background scans and selectively uses foreground scans based on overall scan progress, thereby adjusting the foreground media skip time and cadence to avoid premature or late enabling of foreground scans.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If foreground scans are enabled frequently to ensure data integrity, then data integrity is improved, but host operation performance deteriorates due to increased scan triggering and execution

Engineering Contradiction:

Improvedata integrityVSAvoidhost operation performance

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent implements dynamic adjustment of foreground scan enabling based on real-time monitoring of overall scan progress. The system transitions from static foreground scan scheduling to dynamic control where the foreground scan enable/disable status is adjusted according to whether background scans are catching up to the scheduled scan timeline, thereby resolving the contradiction between data integrity and host operation performance

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system monitors overall scan progress by comparing actual background scan progress against the scheduled scan timeline and uses this feedback to dynamically adjust foreground scan enabling. This closed-loop feedback mechanism ensures data integrity is maintained while optimizing host operation performance by preventing premature or excessive foreground scan triggering

Inventive Principle:

Principle #23Feedback

2Productivity

If foreground scans are disabled to improve host operation performance, then host operation performance is improved, but data integrity may deteriorate due to insufficient scan coverage

Engineering Contradiction:

Improvehost operation performanceVSAvoiddata integrity

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The system dynamically adjusts foreground scan enabling based on real-time monitoring of overall scan progress. The foreground scan enable/disable status is not fixed but adapts according to whether background scans are catching up to the scheduled scan timeline, thereby resolving the contradiction between data integrity and host operation performance

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system monitors overall scan progress by comparing actual background scan progress against the scheduled scan timeline and uses this feedback to dynamically adjust foreground scan enabling. This closed-loop feedback mechanism ensures data integrity is maintained while optimizing host operation performance by preventing premature or excessive foreground scan triggering

Inventive Principle:

Principle #23Feedback

3Reliability

If foreground scans are enabled prematurely to ensure data integrity, then data integrity is improved, but unnecessary scan execution increases wasting time and resources

Engineering Contradiction:

Improvedata integrityVSAvoidscan execution time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The system performs preliminary scheduling of background scans to cover the entire media before foreground scans are needed. By pre-scheduling and executing background scans that catch up to the scheduled scan timeline, the system avoids premature foreground scan triggering and only enables foreground scans when necessary, thereby reducing unnecessary scan execution time and resources

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system monitors overall scan progress by comparing actual background scan progress against the scheduled scan timeline and uses this feedback to dynamically adjust foreground scan enabling. This closed-loop feedback mechanism ensures data integrity is maintained while optimizing host operation performance by preventing premature or excessive foreground scan triggering

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS20250130894A1Dynamically enabling foreground scans of memory blocks

Publication Date: 2025.04.24 MICRON TECHNOLOGY INC

AI summary

Various embodiments provide for dynamically enabling and disabling foreground scans of blocks of a memory device, which can be part of a memory sub-system. For instance, some embodiments provide an improved methodology for triggering foreground media scans of blocks of a memory device without disturbing a maximum idea time of background media scans of blocks of the memory device.