John Petrucci is one of my favorite prog-rock guitarists and fast angular guitar licks like this one is one of the reasons why. John breaks down this 2 note per string arpeggio based flurry for you pretty well, but if you do get lost I’ve included the tabs. This is what John has to say about it from Guitar World:

Today’s lick is a sequence of fast, descending arpeggios based on the E Aeolian mode (E F♯ G A B C D) and performed in a deliberate two-notes-per-string pattern. I use strict alternate picking throughout the entire lick, beginning on a downstroke.

When playing licks or melodies using two notes per string, many guitarists rely almost exclusively on their fret-hand ring and index fingers, even though the pinkie can more easily and comfortably reach most wide-interval stretches. If you find you’re consistently shunning your pinkie during solos, I encourage you to follow my example and advice and practice this lick using your pinkie for the wide-interval stretch at the beginning of each arpeggio. You’ll receive a great pinkie workout, after which you may begin to find yourself more at ease and sure-fingered when performing other licks incorporating wide-interval stretches.