Prime Dependency List for Consistent File System Points

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In multi-partition file systems, maintaining consistent points is inefficient due to the need to write prime segments to all storage units, which is time-consuming and requires excessive storage space, especially when some partitions are read-only or unavailable, leading to prolonged startup times and increased storage needs.

Innovation Solution

A prime dependency list and prime segment write-map are used to selectively write new prime segments only to affected storage units, allowing for the identification of necessary prime segments through a dependency list, reducing the need to verify all segments and power up all storage units during startup.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If prime segments are written to all storage units to mark consistent points, then data consistency across partitions is ensured, but storage space requirements increase and write time is prolonged

Engineering Contradiction:
Improvedata consistencyVSAvoidstorage space
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The patent segments the prime segment writing operation by identifying and writing prime segments only to affected storage units rather than all storage units. The system determines which storage units contain data that changed since the last consistent point and writes prime segments only to those specific units, thereby reducing storage space requirements while maintaining data consistency across the file system.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies local quality by treating different storage units differently based on their specific needs. Instead of uniformly writing prime segments to all storage units, the system identifies affected storage units and writes prime segments only to those locations where consistency is actually required, optimizing storage space usage while ensuring data integrity.

Inventive Principle:
Principle #3Local quality

2Reliability

If prime segments are written to all storage units, then consistent file system views are established, but the time required to write and verify prime segments increases

Engineering Contradiction:
Improvefile system consistencyVSAvoidstartup time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent segments the verification process by identifying only the affected storage units that require prime segment verification rather than verifying all storage units. This segmentation approach significantly reduces the time required during system startup while ensuring that consistency is verified where it matters.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary action by maintaining information about affected storage units during normal operation, so that during startup or consistency checks, the system already knows which storage units need verification. This preliminary tracking eliminates the need to scan and verify all storage units, reducing startup time.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If prime segments are written to unavailable or read-only partitions, then complete consistency coverage is achieved, but write operations fail and time is wasted

Engineering Contradiction:
Improveconsistency coverageVSAvoidwrite efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies dynamics by making the prime segment writing process adaptive to the current state of storage units. The system dynamically determines which storage units are available and writable at the time of the consistency operation, and adjusts its writing strategy accordingly. This dynamic approach prevents wasted write operations on unavailable or read-only partitions while maintaining consistency coverage for accessible storage units.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP2691847B1System and method for maintaining consistent points in file systems using a prime dependency list
Publication Date: 2019.05.01 DELL EMC
  • EP2691847B1 patent drawingFigure 1
  • EP2691847B1 patent drawingFigure 2
  • EP2691847B1 patent drawingFigure 3A

AI summary

According to one embodiment, a request is received for obtaining a consistent point of data stored in a file system of a storage system having a plurality of storage units. In response to the request, retrieving a prime dependency list from a first prime segment stored in a first of the storage units, where the prime dependency list includes information identifying at least a second prime segment stored in a second of the storage units. The first and second prime segments collectively form a prime segment representing a consistent view of the file system. Each of the prime segments listed in the prime dependency list is ascertained in an attempt to generate the consistent point of data.