HDD - Sequential access patterns

• When accessing data sequentially:
• the read head is placed on the first sector
• and data is read as the disk revolves.
• This implies that throughput depends on the RPM of the disk.
  • which means data is read slower as we move to inner tracks (which contain less sectors).
• For long sequential access - the initial seek time is negligible.
• Note: since moving the heads between tracks takes time, we can store the sectors of inner tracks with an offset:

Originally written by guy keren