Numbers To Know medium
What is the approximate seek time (random access) for a traditional spinning Hard Disk Drive (HDD)?
- A approximately 1 ms
- B approximately 100 ms
- C approximately 10 microseconds
- D approximately 10 ms
Answer: D. approximately 10 ms
In a traditional spinning HDD (Hard Disk Drive), the 'seek time' is the physical time required for the mechanical arm to move to the correct data track. For typical high-speed server drives, this takes about 5-10 milliseconds. This mechanical nature imposes a hard limit on performance; because 1 second contains 1,000ms, a drive with a 10ms seek time can only perform about 100 random lookups per second (100 IOPS). This is the fundamental reason why large-scale databases migrated to SSDs, which have no moving parts and can achieve 100,000+ IOPS, representing a 1,000x leap in performance.
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