The difference between LRU and LFU

LRU and LFU are different!

LRU is the least recently used page replacement algorithm (Least recently used), which is the first time to eliminate the longest unused pages!

LFU is the most infrequently used page replacement algorithm (Least frequently used), which is the least visited page in a certain period of time!

For example, the second method of the time t is 10 minutes, if the paging per minute, the main memory block is 3, if the desired page trend is 2 1 2 1 2 3 4

Note that a page break will occur when paging 4 o'clock

If the LRU algorithm, should be changed page 1 (1 pages have not been used) but according to the LFU algorithm should be changed Page 3 (10 minutes, Page 3 is used only once)

It is visible that the LRU key is to see the last time the page was used to schedule the duration of the event,

The key to Lfu is to see how often the page is used within a certain time period!

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