That document certainly states that project.max-shm-memory should be set to 4GB as a minimum. It also then states that "project.max-shm-memory" represent the maximum shared memory available for a project, so the value for this parameter should be greater than sum of all SGA sizes. "If you have 64 G than why you are choosing %50 for PGA? Its too mch? any reason?
So on a 64GB server, intended for 1 instance, I guess I allow 50% PGA and 50% SGA. So I'd set max-shm-memory to 32GB? Maybe 40GB for growth+wiggle room?