How can Belady's anamoly be avoided?

Question

When we increase the number of frames to the process then the number of page fault should decrease but instead the page fault increase sometimes (Belady's anamoly). How this can be avoided?

score 5 · Accepted Answer · answered Aug 04 '15 at 05:27

5

Belady's anomaly is prevalent with a FIFO eviction policy. Every eviction policy will have a pattern that will "break" it. However, there are a few eviction policies that can avoid Belady's.

Random eviction
LRU (Least Recently Used)

Here is more information

answered Aug 04 '15 at 05:27

The Brofessor

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can you please explain random eviction?? – Anurag Singh Aug 04 '15 at 05:39
Random eviction is straightforward. Whenever we need to evict, we select a random page to evict (via a random number generator). No internal structures or metadata needed like FIFO and LRU. – The Brofessor Aug 04 '15 at 05:59

How can Belady's anamoly be avoided?

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