Distributed Storage Parity Update Method for Network Traffic Optimization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing distributed storage systems face performance issues with update writes in erasure-coded data, as they require recalculation of parity data, leading to increased network traffic and reduced performance, especially for small update sizes.

Innovation Solution

A distributed storage system that switches between two parity update methods based on network traffic: full-stripe parity calculation and read-modify-write (RMW) parity calculation, optimizing network usage by selecting the method that minimizes traffic during updates.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If recalculation of parity data is performed for update writes in erasure-coded distributed storage systems, then data protection reliability is maintained, but write performance deteriorates and network traffic increases

Engineering Contradiction:
Improvedata protection reliabilityVSAvoidwrite performance
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The system dynamically switches between two parity update methods (full-stripe recalculation and RMW-based update) based on real-time network traffic conditions. When network traffic is low, full-stripe recalculation is used to ensure data reliability. When network traffic is high, RMW-based updates are used to maintain write performance, thus adaptively resolving the contradiction between reliability and productivity

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the operational parameters of parity update by selecting different calculation methods based on network traffic thresholds. The system monitors network traffic volume and adjusts the parity update strategy accordingly, transforming the fixed reliability mechanism into a flexible parameter-driven approach that can optimize write performance under varying network conditions

Inventive Principle:
Principle #35Parameter changes

2Reliability

If full-stripe parity recalculation is performed for all data units, then data protection reliability is improved, but network traffic volume increases significantly

Engineering Contradiction:
Improvedata protection reliabilityVSAvoidnetwork traffic volume
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

Instead of always performing full-stripe parity recalculation on all data units, the system applies partial action by using RMW-based updates that only recalculate parity for affected data units when network traffic is high. This partial approach reduces network traffic volume while maintaining adequate data protection, resolving the contradiction between reliability and traffic volume

Inventive Principle:
Principle #16Partial or excessive action

3Productivity

If RMW operations are performed on original data and parity data for small update sizes, then write performance is maintained, but network traffic between nodes increases

Engineering Contradiction:
Improvewrite performanceVSAvoidnetwork traffic between nodes
Core Design Contradiction:
ProductivityVSQuantity of substance

Solution Approach 1:

The system dynamically adjusts the parity update strategy based on network traffic conditions. When network traffic is already high, the system switches from RMW operations to full-stripe recalculation, which reduces network traffic between nodes even if it temporarily impacts write performance. This dynamic adjustment resolves the contradiction by adapting to current network conditions

Inventive Principle:
Principle #15Dynamics

Data Source

PatentUS11467908B2Distributed storage system, distributed storage node, and parity update method for distributed storage system
Publication Date: 2022.10.11 HITACHI VANTARA LTD
  • US11467908B2 patent drawing
  • US11467908B2 patent drawing
  • US11467908B2 patent drawing

AI summary

A distributed storage places data units and parity units constituting a stripe formed by divided data into storage nodes in a distributed manner. In reference to determination formulas, either a full-stripe parity calculation method or an RPM parity calculation method is selected so as to minimize an amount of network traffic.