Belady's anomaly

When u use the  FIFO page replacement algorithm, it happens.
even for large number of page numbers the no of page faults increases as compared to the less number of page number in the memory.
It is dependent on the order of page requirement (i.e string-reference). so string-reference is chosen so that minimum page faults occur.

The Belady's anomaly accurs in case of the FIFO page replacement policy in the OS.
When this FIFO is used and the number of page frames are increased in number, then the frames that are required by the program varies in a large range(due to large no of pages) as a result of this the number of page faults increases with the number of frames.

This anomoly oesn't occur in the LRU(least recently used) scheduling algorithm.

The Belady's anomaly accurs in case of the FIFO page replacement policy in the OS.
When this FIFO is used and the number of page frames are increased in number, then the frames that are required by the program varies in a large range(due to large no of pages) as a result of this the number of page faults increases with the number of frames.

This anomoly oesn't occur in the LRU(least recently used) scheduling algorithm.

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Usually, on increasing the number of frames allocated to a process virtual memory, the process execution is faster, because fewer page faults occur. Sometimes, the reverse happens, i.e., the execution time increases even when more frames are allocated to the process. This is Beladys Anomaly. This is true for certain page reference patterns.