cpu time

1s -> 10^3ms -> 10^6us -> 10^9ns

1. cpu's speed depend on frequency, one 3Gz core can execute 3x10^9 command
   convert to time, one command need about 0.33ns. To human like a blink 0.4s.
2. level-1 cache read once need 0.5ns, to human like a heart beat 1.3s
3. branch predict need 5ns, about 13s to human
4. level-2 cache read once need 7ns, about 18.3s to human
5. mutex-lock lock or unlock need 25ns, about a minute to human
6. memory address searching need 100ns, about 4 minute to human
7. cpu switch context need 1500ns (1.5us), about a hour to human
8. transfer data in a 1Gpbs web 2kb need 20us, about 14.4h to human
9. SSD random read need 120us, about 4.5d to human
10. read data from meory a sequencial 2mb data need 250us, about 7.5d to human
11. SSD read data a sequencial 1mb data need 1ms, about a month to human
12. hard disk read a sequencial 1mb data need 20ms, about 20 month to human
13. different world web a ping need 120ms, about 12.5 year to human
14. reboot vm need 4s, about 300y to human
15. reboot machine need 5minute, about 25000y……