io - How many physical I/O operations required to write one block in RAID 5? -

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i understand sum of read , write rates equals i/o rate per second in raid 5 design, how may go calculating how many physical i/o operations take write 1 block exactly?

thanks!

according this article, takes 4 psychical i/o operations whenever i/o operation done application. these operations follows:

  1. read block needs modified
  2. read parity block
  3. update data block
  4. update parity block

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