When a Page is Requested ...

• If requested page is not in pool:

  • Choose a frame for replacement; pin_count := 1
  • If frame is dirty, write it to disk
  • Read requested page into chosen frame

• Else:

  • increment pin_count

• Return its address.

• If requests can be predicted (e.g., sequential scans)

pages can be pre-fetched several pages at a time!

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