perpetually vs incessantly

perpetually and incessantly both are adverbs.

Word	Noun	Adjective	Verb	Adverb
perpetually	No	No	No	Yes
incessantly	No	No	No	Yes

As adverbs, perpetually and incessantly are synonyms defined as:

Other synonyms of perpetually include always, constantly, forever.

perpetually (adverb)	incessantly (adverb)
invariably	invariably
everlastingly; for all time	with unflagging resolve