Partial Mapping Table Caching for Memory Controller Cache Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional memory systems face delays in processing host requests due to inefficient caching of mapping information between physical and logical addresses, leading to suboptimal cache hit rates and processing speeds.
Innovation Solution
A memory system and controller that employ a partial caching technique, where a partial mapping table is maintained with selected mapping information, and updates to reference-related parameters are performed based on data size, with cache replacement policies optimizing the caching status to ensure quick processing and high cache hit rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a complete mapping table is cached in the memory controller, then cache hit rate improves, but memory controller complexity and power consumption increase
Solution Approach 1:
The mapping table is divided into multiple segments or pages. Only the currently needed segments are cached in the memory controller, while other segments remain in the memory device. This segmentation allows the system to maintain high cache hit rates for active data without caching the entire mapping table, thereby reducing controller complexity and power consumption.
Solution Approach 2:
Instead of caching the complete mapping table (excessive action), the system caches only the necessary portion (partial action) - specifically, the mapping information for currently accessed or frequently accessed data. This partial caching approach achieves sufficient cache hit rates while avoiding the overhead of maintaining a complete cache.
2Adaptability or versatility
If mapping table size increases, then address mapping coverage improves, but access time increases
Solution Approach 1:
The large mapping table is segmented into multiple smaller pages or blocks. The system loads only the relevant segments into the controller's cache when needed, enabling fast access to current data while maintaining the capability to map large address spaces by loading additional segments on demand.
Solution Approach 2:
The system performs preliminary actions by pre-loading mapping table segments that are likely to be needed soon, or loading segments in advance before they are actually required. This reduces access time when the data becomes needed while still supporting large address mapping coverage.
3Productivity
If all mapping information is cached, then processing speed improves, but power consumption increases
Solution Approach 1:
The system performs partial caching of mapping information - enough to maintain acceptable processing speed for current operations, but not so much as to cause excessive power consumption. The cache is dynamically adjusted to contain only the necessary mapping entries for active data access patterns.
Solution Approach 2:
The caching strategy is dynamic rather than static. The memory controller adjusts which mapping table segments are cached based on current access patterns, workload characteristics, and power availability. This dynamic adaptation allows the system to optimize the balance between processing speed and power consumption in real-time.
Data Source
AI summary
Embodiments of the present invention relate to a memory system, a memory device, a memory controller and an operating method thereof. A partial mapping table including some of plural pieces of mapping information between physical addresses and logical addresses, which are included in a mapping table stored in the memory device, is cached, a piece of mapping information corresponding to data indicated by a command is referred to in the partial mapping table, and whether to perform an update for a reference-related parameter of the piece of mapping information is controlled depending on a size of the data, thereby improving cache efficiency for mapping informations for processing a request from a host and through this, increasing the success rate of a cache hit.