Like all modern day consoles, the PlayStation Vita's SoC contains multiple CPU cores but not all of these cores can be used by games and homebrew. Out of the console's 4 cores, one core (CPU3) is dedicated exclusively to handling system processes in a similar fashion to the Nintendo 3DS & Switch which effectively slashes the Vita’s processing power by 25%.

However, it was noted that this core generally hovers around 10-15% utilization while playing games which prompted Team CBPS member Graphene to come up with a solution to allow its usage in commercial games and homebrew!
Team CBPS Forum Thread (installation instructions + more info)

GitHub Release Page (download page)

Source