HDD - Random access patterns
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- For random access - the seek time becomes very dominant.
- Consider a disk that can read 100MB per second.
- The time for a seek could be 5 milli-seconds.
- The time to read 4KB of data will be 0.03 milli-seconds.
- even if we need to read 1MB of data - the read time will be 1 milli-second.
- Note: caching will be almost meaningless, for a system
that contains 100TB of data (for instance).