Transactional Memory Coherence Control via Privilege State Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In multiprocessor computing environments, the increasing number of CPU cores leads to scalability issues due to shared resource contention, particularly with traditional synchronization mechanisms like semaphores, which result in sub-linear scaling and inefficiencies, and hardware Transactional Memory (TM) solutions are needed to improve performance and ease of use.

Innovation Solution

A computer-implemented method in a transactional memory environment identifies selected processors and their coherence privilege state indicators to determine behavioral patterns, allowing for optimized coherence privilege control, reducing transactional aborts and improving resource management through intelligent abort policies and privilege state modifications.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional synchronization mechanisms like semaphores are used, then resource access control is achieved, but scalability deteriorates due to sub-linear scaling curves and hot spots

Engineering Contradiction:

Improveresource access controlVSAvoidscalability

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent extracts the synchronization control logic from traditional software-based semaphores and relocates it to hardware transactional memory mechanisms. This extraction eliminates the scalability bottleneck by moving the critical section management to hardware level, where multiple processors can execute transactions concurrently without software intervention, thus resolving the contradiction between reliable resource control and system scalability

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the mechanical software-based semaphore system with a hardware-based transactional memory system. The hardware TM mechanism uses specialized circuitry to manage transactional memory operations, providing both the reliability of controlled resource access and the scalability of hardware-level parallelism, thereby substituting the software mechanical system with a hardware-based solution

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Productivity

If fine-grained locking is implemented to improve software scalability, then resource access efficiency is improved, but device complexity increases significantly

Engineering Contradiction:

Improvesoftware scalabilityVSAvoidlocking mechanism complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent implements self-service through hardware automatic conflict detection and transaction management. The transactional memory hardware automatically monitors memory access patterns, detects conflicts between concurrent transactions, and manages the transaction lifecycle without requiring complex software locking mechanisms. This self-service capability achieves fine-grained scalability while eliminating the complexity of manual locking implementation

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent inverts the traditional approach by instead of having software manage locks, the hardware automatically manages transactional memory operations. This inversion transfers the complexity from software to hardware, where the complexity can be handled more efficiently through dedicated circuitry, thereby achieving scalability without increasing software or system complexity

Inventive Principle:

Principle #13The other way round (Inversion)

3Speed

If hardware interconnects operate at higher bandwidth and lower latency, then data transfer speed is improved, but physical dimension constraints and speed of light limitations still bound performance

Engineering Contradiction:

Improvedata transfer speedVSAvoidchip physical dimension

Core Design Contradiction:

SpeedVSLength of moving object

Solution Approach 1:

The patent merges the interconnect communication function with the transactional memory management function by implementing coherence protocols directly within the transactional memory hardware. This merging eliminates the need for separate high-speed interconnect communication for coherence management, as the coherence control is integrated into the TM subsystem, thereby reducing the effective communication distance and mitigating the impact of physical dimension constraints on data transfer speed

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS10120803B2Transactional memory coherence control

Publication Date: 2018.11.06 INTERNATIONAL BUSINESS MACHINE CORPORATION

AI summary

A computer-implemented method includes, in a transactional memory environment comprising a plurality of processors, identifying one or more selected processors and identifying one or more coherence privilege state indicators. The one or more coherence privilege state indicators are associated with the one or more selected processors. A coherence privilege behavioral pattern is determined based on the one or more coherence privilege state indicators. A corresponding computer program product and computer system are also disclosed.