computing vs command processing overhead time

computing and command processing overhead time both are nouns.

Word	Noun	Adjective	Verb	Adverb
computing	Yes	No	No	No
command processing overhead time	Yes	No	No	No

computing (noun)	command processing overhead time (noun)
the procedure of calculating; determining something by mathematical or logical methods	(computer science) the processing time required by a device prior to the execution of a command
the branch of engineering science that studies (with the aid of computers) computable processes and structures