TCP Connection Migration Scheduling for Cluster I/O Efficiency

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current cluster-based architectures face inefficiencies in data delivery due to the need for data copies between nodes and the high cost of TCP/IP connection migrations, particularly for large and small I/O operations.

Innovation Solution

The method involves efficient scheduling of TCP connection migrations and allowing I/O operations to coexist as either TCP handoff or remote operations on the same connection, with connection migration occurring after completing I/O requests, and determining whether to handoff or process requests based on accumulated statistics to optimize performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If TCP/IP connection migration is performed to enable direct data delivery to client, then data delivery efficiency is improved, but connection migration cost increases and performance degrades for small I/O requests

Engineering Contradiction:
Improvedata delivery efficiencyVSAvoidconnection migration time
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The system performs preliminary actions by maintaining the connection at the receiving node and only migrating when statistically beneficial. The node accumulates I/O request statistics and determines optimal migration timing in advance, rather than migrating immediately upon receiving each I/O request. This preliminary assessment prevents unnecessary migrations for small I/O operations while preparing for efficient direct delivery when appropriate.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system changes the parameter of connection ownership dynamically based on I/O patterns. The connection can exist in different states: hosted at the receiving node for small I/Os, or migrated to the executing node for large I/Os. This parameter change is driven by statistical analysis of I/O request sizes and patterns, allowing the system to adapt the connection location to match the workload characteristics.

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If data copies are moved between cluster nodes for remote operations, then any node can handle any I/O request, but performance is limited for large I/O operations

Engineering Contradiction:
Improvenode flexibilityVSAvoidI/O performance
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The system segments I/O operations into two categories: small I/Os handled as remote operations with data copying, and large I/Os handled as handoff operations with connection migration. This segmentation allows each type of operation to use the most appropriate handling method, maximizing both versatility and performance for different workload types.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system dynamically determines the handling method for each I/O request based on real-time statistical analysis. The decision between remote operation and handoff operation is not fixed but adapts to the specific I/O pattern, request size, and current system state, allowing optimal performance across varying workload conditions.

Inventive Principle:
Principle #15Dynamics

3Speed

If TCP connection is migrated to the node executing I/O, then reply data is sent directly to client, but connection migration is expensive and limits performance for small I/O requests

Engineering Contradiction:
Improvereply data delivery speedVSAvoidconnection management complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The receiving node acts as an intermediary that initially hosts the connection and makes intelligent decisions about whether migration is necessary. This intermediary role allows the system to filter out unnecessary migrations by analyzing I/O patterns before committing to connection migration, thereby reducing overall complexity while maintaining fast direct delivery when beneficial.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentUS7565446B2Method for efficient delivery of clustered data via adaptive TCP connection migration
Publication Date: 2009.07.21 INNOVATIONS IN MEMORY LLC
  • US7565446B2 patent drawing
  • US7565446B2 patent drawing
  • US7565446B2 patent drawing

AI summary

The present invention relates generally to a method for efficient I/O handling in a cluster-based architecture. According to one aspect, the invention enables efficient scheduling of TCP connection migrations within a cluster. According to another aspect, the invention enables I/Os performed as TCP handoff operations to coexist on the same TCP/IP connection with I/Os performed as remote operations.