Limiting snapmirror bandwith - CPU behavior?

Hello fellow SAN admins, I've got question concerning the CPU behavior when limiting snapmirrors: actually our FAS is facing some CPU issues (over 80% CPU usage constantly), and I was thinking about removing the snapmirror limitation, in order to "discharge" the CPU. Can someone confirm if there's an impact (even minimal) in the CPU when "software-limiting" the snapmirrors? thanks!!