pga_aggregate_target question in CDB environment

Hi

19.16 RAC

I have pdbs: pdb1, pdb2, pdb3

Let's say, I have set pga_aggregate_target to a value of 10G for CDB (pga_aggregate_limit is then 20G by default).

And I do not set this value for any of the PDB-s. So pdb1, pdb2, pdb3 all have CDB default value of 10G.

Does this mean that CDB and all of the pdb's combined have max pga_aggregate_target set to 10G ? (so max host memory is taken 10G)

Or does it mean that each of the PDB's and CDB - all of these have 10G of PGA each..? (so in total, 40G of host memory can be allocated)