What are the cache elimination mechanisms?

The cache elimination mechanisms include first-in-first-out, least recently used, least used, least recently used weighted, least frequently used, random elimination, cost-based elimination, etc. Detailed introduction: 1. First in, first out (FIFO): the earliest data that enters the cache is eliminated first; 2. Least Recently Used (LRU): the least recently used data is eliminated first; 3. Least Used (LFU): The data with the lowest frequency of use is eliminated first; 4. Least Recently Used Weighting (LRU-K): combines the ideas of LRU and LFU, etc.

Operating system for this tutorial: Windows 10 system, Dell G3 computer.

The cache elimination mechanism refers to a mechanism that selects which cached data to be removed or replaced according to a certain strategy when the cache space is insufficient. Common cache elimination mechanisms include the following:

• First in, first out (FIFO): The earliest data that enters the cache is eliminated first.

• Least Recently Used (LRU): The least recently used data is eliminated first.

• Least Used (LFU): Data with the lowest frequency of use is eliminated first.

• Least Recently Used Weighting (LRU-K): Combining the ideas of LRU and LFU, the least recently used data is eliminated, but the frequency of use in the past period of time will be considered.

• Least Frequently Used (MFU): The most frequently used data is eliminated first.

• Random elimination (Random): Randomly select the data to be eliminated.

• Cost-based elimination (CBA): Elimination is based on the cost and value of data. Data with high cost or low value will be eliminated first.

Different elimination mechanisms are suitable for different application scenarios and requirements. Choosing an appropriate elimination mechanism can improve cache efficiency and hit rate, thereby improving system performance. In actual applications, the elimination strategy can also be customized according to specific circumstances to meet specific business needs.

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