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Overview of techniques to speed up access to data stored on hard disk

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• General approaches to speed up access to data stored on disks
  • Techniques (and tricks):

    Placement: Place sectors of the same blocks in the same cylinder Example: (Watch how the disk write multiple sectors of the same block at same time !!!) Allocate blocks of the same file in same or nearby cylinders (That's what happens when you perform a disk de-fragmentation) Striping (next webpage) Scheduling (next webpage) Pre-fetching (next webpage)