ORA-00855 when Windows have 40G free memory

RDBMS 19.12

Windows 2019

Upgraded to 19c.

Hi,

SGA_TARGET=215G

SGA_MAX_TARGET=215G

PGA_AGGREGATE_TARGET=32G

PGA_AGGREGATE_LIMIT=64G

dedicated server is in use

Windows box has a total RAM of 312G.

Statspack shows that we should increase PGA_AGGREGATE_TARGET to 39G, when trying that we get:

SQL> ALTER SYSTEM SET PGA_AGGREGATE_LIMIT=78G scope=both;

System altered.

SQL> ALTER SYSTEM SET PGA_AGGREGATE_TARGET = 39G scope=both;

ALTER SYSTEM SET PGA_AGGREGATE_TARGET = 39G scope=both

*

ERROR at line 1:

ORA-02097: parameter cannot be modified because specified value is invalid

ORA-00855: PGA_AGGREGATE_TARGET cannot be set because of insufficient physical