Adaptive Last Level Cache Utilization Strategy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-level multi-core cache systems, the Last Level Cache (LLC) utilization efficiency is compromised due to high cache miss rates, leading to resource wastage and performance degradation as threads compete for cache space, resulting in inefficient utilization and potential cache pollution.
Innovation Solution
A cache system and operating method that adaptively adjust the utilization strategy of upper-level cache units to the LLC by using a directory, counters, and a register to track and respond to utilization status, access numbers, and access hit numbers, allowing for flexible management of cache resources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If threads compete for LLC space without adaptive control, then cache space is available for multiple threads, but LLC utilization efficiency deteriorates and cache pollution occurs
Solution Approach 1:
The patent implements dynamic adjustment of LLC allocation strategies based on real-time monitoring of upper-level cache hit rates. The system transitions from static cache allocation to dynamic control where the LLC utilization strategy is continuously adapted according to the performance characteristics of individual upper-level caches, thereby improving overall LLC utilization efficiency while preventing cache pollution from inefficient accesses.
Solution Approach 2:
The patent employs feedback mechanisms by monitoring the hit rates of upper-level caches and using this information to adjust LLC allocation policies. The system records hit rate information and uses it as feedback to dynamically modify the utilization strategy, creating a closed-loop control system that optimizes cache performance and prevents harmful cache pollution effects.
2Productivity
If static cache allocation is used, then system simplicity is maintained, but system performance deteriorates due to inability to adapt to varying access patterns
Solution Approach 1:
The patent enables the cache system to self-adjust its behavior by automatically monitoring upper-level cache hit rates and autonomously modifying LLC allocation strategies without external intervention. The cache management unit records performance metrics and independently decides on strategy adjustments, allowing the system to improve performance through self-service adaptation while keeping the control logic integrated within the cache structure.
Solution Approach 2:
The patent changes operational parameters of the cache system dynamically based on monitored performance data. Specifically, it adjusts the LLC utilization strategy parameters according to upper-level cache hit rates, transforming the cache system from a fixed-parameter design to a variable-parameter system that adapts to changing workload characteristics, thereby improving performance without requiring complete redesign of the cache architecture.
Data Source
AI summary
The present disclosure provides a cache system and an operating method thereof. The system includes an upper-level cache unit and a last level cache (LLC). The LLC includes a directory, a plurality of counters, and a register. The directory includes a status indicator recording a utilization status of the upper-level cache unit to the LLC. The counters are used to increase or decrease a counting value according to a variation of the status indicator, record an access number from the upper-level cache unit, and record a hit number of the upper-level cache unit accessing the LLC. According to the counting value, the access number, and the hit number, the first parameters of the register are controlled, so as to adjust a utilization strategy to the LLC.