Unable to decrease SGA on 10g

Question

Hello Gurus
I have an Oracle 10g database on Solaris machine . following are the results of show SGA
Total System Global Area 1191182336 bytes
Fixed Size 2028080 bytes
Variable Size 355208656 bytes
Database Buffers 819200000 bytes
Redo Buffers 14745600 bytes
I want to decrease the SGA to 600 mb only but when i gave
SQL> alter system set sga_max_size=600m;
alter system set sga_max_size=600m
ERROR at line 1:
ORA-02095: specified initialization parameter cannot be modified
then i decide to make changes in init.ora file . i put
sga_max_size = 600m
but that too of no use i got
Specified value of sga_max_size is too small, bumping to 1103101952
in alert log file
please suggest what i'm doing wrong and what should be the proper way to do it
thanks

Answer 1

Hi,
sga_max_size = 600m
but that too of no use i got
Specified value of sga_max_size is too small, bumping to 1103101952
in alert log fileHow do you expect to reduce your SGA to 600 MB if only your buffer cache is 800 MB big?
To reduce the SGA_MAX_SIZE to 600MB you need to reduce the size of all SGA internal memory areas to use 600 MB or less (I'm talking about the sum of all this areas, no each one):
- The shared pool
- The large pool
- The Java pool
- The buffer cache
- The Streams pool
- The Log Buffer
All this memory areas together are the SGA.
Regards,
Francisco Munoz Alvarez
www.oraclenz.com