page_title: Hard disk drive performance characteristics
section_title: Access time
hierarchical_section_title: Hard disk drive performance characteristics / Access time
caption_attribution_description: Čeština: Detailní pohled na hlavu pevného disku
context_page_description: Higher performance in hard disk drives comes from devices which have better performance characteristics. These performance characteristics can be grouped into two categories: access time and data transfer time.
context_section_description: The access time or response time of a rotating drive is a measure of the time it takes before the drive can actually transfer data. The factors that control this time on a rotating drive are mostly related to the mechanical nature of the rotating disks and moving heads. It is composed of a few independently measurable elements that are added together to get a single value when evaluating the performance of a storage device. The access time can vary significantly, so it is typically provided by manufacturers or measured in benchmarks as an average.
  The key components that are typically added together to obtain the access time are:
  Seek time
  Rotational latency
  Command processing time
  Settle time
caption: A hard disk head on an access arm resting on a hard disk platter
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