Re: SGA

i did
sqlplus "/ as sysdba"
startup
but i had an error :
ORA-00824: cannot set sga_target due to exixting internal settings, see alert log for more information

in my alert log :

Thu Nov 29 12:59:13 2007
Memory Notification: Library Cache Object loaded into SGA Heap size 2154K exceeds notification threshold (2048K) Details in trace file c:\oracle\product\10.2.0\admin\sim\bdump
\sim_s001_3888.trc

KGL object name :XDB.XDbD/PLZ01TcHgNAgAIIegtw==

Thu Nov 29 12:59:14 2007
Memory Notification: Library Cache Object loaded into SGA Heap size 2201K exceeds notification threshold (2048K) Details in trace file c:\oracle\product\10.2.0\admin\sim\bdump
\sim_s001_3888.trc

KGL object name :XDB.XDZynXpO5DTv2jNMI2jLTZZA==

Thu Nov 29 15:48:01 2007
Starting background process EMN0
EMN0 started with pid=118, OS id=3536
Thu Nov 29 15:48:02 2007
Shutting down instance: further logons disabled Thu Nov 29 15:48:02 2007
Stopping background process CJQ0
Thu Nov 29 15:48:02 2007
Stopping background process QMNC
Thu Nov 29 15:48:04 2007
Stopping background process MMNL
Thu Nov 29 15:48:05 2007
Stopping background process MMON
Thu Nov 29 15:48:06 2007
Shutting down instance (immediate)
License high water mark = 14
Thu Nov 29 15:48:06 2007
Stopping Job queue slave processes
Thu Nov 29 15:48:06 2007
Job queue slave processes stopped
The value of parameter db_block_buffers is below the required minimum
The new value is ((4MB * the number of cpus)/db_block_size) Cannot set sga_target with db_block_buffers set Thu Nov 29 15:52:12 2007
Waiting for dispatcher 'D000' to shutdown Thu Nov 29 15:54:13 2007
All dispatchers and shared servers shutdown Thu Nov 29 15:54:14 2007
ALTER DATABASE CLOSE NORMAL
Thu Nov 29 15:54:14 2007
SMON: disabling tx recovery
SMON: disabling cache recovery
Thu Nov 29 15:54:15 2007
Shutting down archive processes
Archiving is disabled
Archive process shutdown avoided: 0 active Thread 1 closed at log sequence 7
Successful close of redo thread 1
Thu Nov 29 15:54:15 2007
Completed: ALTER DATABASE CLOSE NORMAL
Thu Nov 29 15:54:15 2007
ALTER DATABASE DISMOUNT
Completed: ALTER DATABASE DISMOUNT
ARCH: Archival disabled due to shutdown: 1089 Shutting down archive processes
Archiving is disabled
Archive process shutdown avoided: 0 active ARCH: Archival disabled due to shutdown: 1089 Shutting down archive processes
Archiving is disabled
Archive process shutdown avoided: 0 active Received on Thu Nov 29 2007 - 07:51:13 CST