Page Faults with FIFO Page Replacement Algorithm

To determine the number of page faults that would occur using the FIFO (First-In, First-Out) page replacement algorithm for the given reference string and three-page frames, we need to simulate the process step by step.

The reference string is as follows: 7, 0, 1, 2, 0, 3, 0, 4, 2, 3, 0, 3, 2, 1, 2, 0, 1, 7, 0, 1

Step 1: Initialize an empty set for the page frames and set the count of page faults to 0.

Step 2: Iterate through the reference string and for each page:

- Check if the page is already present in the page frames.
- If it is present, move to the next page.
- If it is not present, check if there is an empty page frame available.
- If there is an empty page frame, allocate the page to the empty frame and move to the next page.
- If there is no empty page frame, select the oldest page in the page frames (the one that arrived first) and replace it with the current page. Increment the count of page faults.

Step 3: Repeat Step 2 until all pages in the reference string are processed.

Step 4: Count the total number of page faults that occurred during the simulation.

Let's go through the simulation with the given reference string and three-page frames:

- Initially, the page frames are empty.
- The first page, 7, is not present, so it is allocated to an empty frame. (Page faults: 1)
- The second page, 0, is not present, so it is allocated to an empty frame. (Page faults: 2)
- The third page, 1, is not present, so it is allocated to an empty frame. (Page faults: 3)
- The fourth page, 2, is not present, so it is allocated to an empty frame. (Page faults: 4)
- The fifth page, 0, is already present in a frame, so no page fault occurs.
- The sixth page, 3, is not present, so the oldest page (7) is replaced with 3. (Page faults: 5)
- The seventh page, 0, is already present in a frame, so no page fault occurs.
- The eighth page, 4, is not present, so the oldest page (0) is replaced with 4. (Page faults: 6)
- The ninth page, 2, is already present in a frame, so no page fault occurs.
- The tenth page, 3, is already present in a frame, so no page fault occurs.
- The eleventh page, 0, is already present in a frame, so no page fault occurs.
- The twelfth page, 3, is already present in a frame, so no page fault occurs.
- The thirteenth page, 2, is already present in a frame, so no page fault occurs.
- The fourteenth page, 1, is already present in a frame, so no page fault occurs.
- The fifteenth page, 2, is already