Dynamic Quorum Adjustment for Distributed System Availability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Distributed computing systems face instability and failure when the number of active nodes falls below the required quorum, leading to inability to perform functions, despite having sufficient resources.

Innovation Solution

Implementing a dynamic quorum system that adjusts the voting privileges of cluster nodes based on their participation state, allowing the system to sustain more node crashes and continue operations by dynamically reducing or adjusting the quorum value when necessary.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a fixed quorum value is used in a distributed system, then the system maintains strict consensus requirements and prevents unauthorized actions, but the system becomes unable to perform functions when the number of active nodes falls below the quorum threshold

Engineering Contradiction:
Improveconsensus integrityVSAvoidsystem functionality
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent implements dynamic quorum adjustment by allowing the quorum value to change based on the current number of active nodes. When nodes fail or join, the quorum threshold dynamically adapts to maintain system functionality while preserving consensus integrity through controlled adjustment mechanisms.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the quorum parameter from a fixed value to a dynamic value that adjusts based on system state. This parameter change allows the quorum threshold to scale with the number of active nodes, preventing system shutdown while maintaining security through bounded adjustment rules.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If the quorum value is reduced to maintain functionality with fewer nodes, then the system can continue operating, but the security margin and consensus strength are weakened

Engineering Contradiction:
Improvesystem availabilityVSAvoidconsensus strength
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The system implements feedback mechanisms that monitor the number of active nodes and automatically adjust the quorum value accordingly. This feedback loop ensures that quorum reduction only occurs when necessary and stops when sufficient nodes are restored, maintaining security margins while ensuring availability.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent incorporates safety buffers and boundary conditions in the quorum adjustment logic that prevent excessive reduction of quorum values. These pre-established protective measures ensure that even during dynamic adjustment, the system maintains sufficient consensus strength and security margins.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

3Reliability

If a majority quorum (n/2 + 1) is required for a cluster of n nodes, then the system ensures strong consensus, but the system fails completely when node losses approach the majority threshold

Engineering Contradiction:
Improveconsensus securityVSAvoidsystem resilience
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent transforms the static majority quorum requirement into a dynamic threshold that adapts to the current cluster size. This dynamic approach allows the system to maintain consensus security while becoming resilient to node failures, as the quorum requirement scales with the number of active nodes rather than failing at a fixed threshold.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentUS10169097B2Dynamic quorum for distributed systems
Publication Date: 2019.01.01 MICROSOFT TECHNOLOGY LICENSING LLC
  • US10169097B2 patent drawing
  • US10169097B2 patent drawing

AI summary

Managing a distributed system. Embodiments may allow for a quorum to dynamically change the quorum vote. One example is illustrated in a method. The method includes determining a change to a voter's level of participation in a cluster. A quorum of voters changes the voter's voting privileges, based on the change in the voter's level of participation.