The sonnet by Petrarch, called ‘Voi ch’ascoltate in rime sparse il suono’ in Italian and sometimes translated as “You who hear the sound, in scattered rhymes,” is a classic Petrarchan sonnet, in the form of an octave, consisting of eight lines in the form of two open quatrains, and a sestet, consisting of six lines with two rhyme sounds, with no fixed order to the use of the rhyme sounds.  The final six lines of the poem constitute the sestet an the first eight lines of the poem constitute the octave.

If you are trying to analyse the meter of an Italian poem, even if you don’t know Italian, it’s worth looking at the original to get a sense of the sound pattern, as not all English translations follow the rhyme scheme of the Italian. Technically, the translation you cite is written in free verse.