Nonvolatile Memory Data Migration via LBA Access Patterns

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing memory systems face inefficiencies in data migration between Multi-Level Cell (MLC) and Single Level Cell (SLC) areas of non-volatile memory, leading to suboptimal data processing speeds during read operations.

Innovation Solution

A memory system with a non-volatile memory comprising a main area and cache areas, where a controller manages data migration based on a list of logical block addresses (LBAs) arranged by read data access frequency, moving frequently accessed data from the MLC area to the SLC area for faster processing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If data is migrated from MLC area to SLC area based on access frequency, then read access speed is improved, but migration overhead and system complexity increase

Engineering Contradiction:

Improveread access speedVSAvoidmigration management complexity

Core Design Contradiction:

SpeedVSDevice complexity

Solution Approach 1:

The system performs preliminary migration of frequently accessed data from MLC to SLC areas before actual read operations occur. The read manager continuously monitors access patterns and proactively migrates data that is likely to be accessed soon, ensuring high-speed access is already in place when read operations occur, rather than migrating data reactively when access is needed

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements a feedback mechanism where the read manager monitors read access patterns to data in the MLC area and uses this information to determine which data should be migrated to the SLC area. The list of LBAs is updated based on access frequency, creating a closed-loop system that continuously optimizes data placement based on actual usage patterns

Inventive Principle:

Principle #23Feedback

2Speed

If data migration is performed continuously to maintain fast access, then read performance is improved, but power consumption and write overhead increase

Engineering Contradiction:

Improvedata processing speedVSAvoidpower consumption

Core Design Contradiction:

SpeedVSUse of energy by moving object

Solution Approach 1:

Instead of continuous migration, the system performs data migration periodically based on monitored access patterns. The read manager accumulates access frequency information over time intervals and triggers migration operations at periodic intervals or when migration opportunities are detected, rather than continuously monitoring and migrating data in real-time

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The system migrates only the necessary portion of data - specifically, frequently accessed data identified through the LBA list - rather than migrating all data or performing exhaustive migration operations. This partial action approach ensures sufficient fast-access data is available in the SLC area without the overhead of migrating unnecessary data

Inventive Principle:

Principle #16Partial or excessive action

Data Source

PatentUS10866898B2Method and apparatus for migrating data between nonvolatile main memory and first or second caches

Publication Date: 2020.12.15 SK HYNIX INC

AI summary

A memory system includes a non-volatile memory including a main area and a first cache area; and a controller suitable for controlling the non-volatile memory and including a second cache area. The controller includes a read manager suitable for performing a migration operation of moving data stored in the main area into the first cache area based on a list storing a plurality of logical block addresses (LBAs) based on a read data access pattern.