Don't make cache too complex: A simple probability-based cache management scheme for SSDs

Area of Science:

• Computer Engineering
• Data Storage Technologies
• Memory Systems

Background:

• Solid-state drives (SSDs) are prevalent in computer systems, driven by cost reductions through smaller feature sizes and multi-level cell technologies.
• Increasing bits per cell in flash memory degrades SSD performance and reliability.
• Non-volatile memory (NVM) caches are used in SSDs to mitigate write latency and reduce flash erase operations.

Purpose of the Study:

• To propose and evaluate ProCache, a novel NVM cache management scheme for SSDs.
• To enhance NVM cache utilization by managing data entrance decisions.
• To offer a simple and cost-effective solution compared to existing techniques.

Main Methods:

• ProCache employs random probability testing for cache-entrance decisions.
• The scheme is motivated by the principle that hot data will likely enter the cache, while cold data will not.
• Performance evaluation compares ProCache against a reference counter-based cache management scheme.

Main Results:

• ProCache demonstrates comparable performance to more complex cache management schemes.
• The proposed scheme effectively increases NVM cache utilization.
• The simplicity of ProCache allows for easier implementation and lower costs.

Conclusions:

• ProCache is an effective and simple NVM cache management strategy for SSDs.
• The random probability approach successfully balances cache utilization and performance.
• This technique offers a viable, low-cost alternative for improving SSD performance.