Put those times on a human scale by setting 1ns CPU time = 1s human time

  • a clock cycle is ~0.1-0.2s, which is more or less instantaneous for humans. This could be, for example, the time to add 2 small numbers that you already have in transistors.
  • If you need to read them off of a page in front of you (L1/L2 cache), that could take a few seconds
  • A System Call (系统调用) takes a few minutes
  • Context Switch is an hour or two
  • HTTP Request takes several hours
  • You need to wait a day to read something from SSD
  • Writing to SSD it’s gonna be in the mail for around a week
  • Seek time of HDD is like 2 months
  • Data over the network from another continent that’s a few years
  • TLS handshake is like a decade
  • Transfer 1GB over network in same cloud region - that’s like 3 centuries