SGA Sizing (SGA_TARGET)

Normally, SGA is tuned automatically by the Oracle database if Automatic Memory Management is enabled. But a DBA can still monitor the size of SGA and find out if it is at the optimal size.

SQL> select * from v$sga_target_advice order by sga_size;

SGA_SIZE SGA_SIZE_FACTOR ESTD_DB_TIME ESTD_DB_TIME_FACTOR ESTD_PHYSICAL_READS

290 .5 448176 1.6578 1636103

435 .75 339336 1.2552 1636103

580 1 201866 1 513881

725 1.25 201866 1 513881

870 1.5 201866 1 513881

1015 1.75 201866 1 513881

1160 2 201866 1 513881

Based on a similar analysis in the Total Memory Sizing section, the current setting of SGA_TARGET is already optimal.