Terminology: opposite the “zero copy”?

Question

We are comparing some code that we converted to use sendfile (), the linux zero-copy system call. What is the term for the traditional read () / write () loop that sendfile () replaces? Ie, in our report I want to say: "zerocopy is X milliseconds, and Y is milliseconds." Which word / phrase should be used?

Answer 1

"Traditional approach to copying data"

Answer 2

Programmed I/O (PIO) would be appropriate, I think.

Answer 3

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