????????
????[oracle@focorcl-ogg01 database]$ sqlplus / as sysdba
????SQL*Plus: Release 11.2.0.4.0 Production on Thu Jul 7 23:51:15 2016
????Copyright (c) 1982?? 2013?? Oracle.  All rights reserved.
????Connected to an idle instance.
????SQL> startup;
??????????м?????????κη????alert_orcl.log??????κ??????
???????
????*.log_archive_dest_1='location=/backup/redo/archive/'
????*.log_archive_format='ARCH_%t_%s_%r.ARC'
????*.memory_max_target=20480G
????*.memory_target=20480G
????[oracle@focorcl-ogg01 trace]$ cat /proc/meminfo
????MemTotal:       49385184 kB
????MemFree:        39167292 kB
??????????48G?????oracle?????????20480G.
???????
????[oracle@focorcl-ogg01 trace]$ sqlplus / as sysdba
????SQL*Plus: Release 11.2.0.4.0 Production on Thu Jul 7 23:59:37 2016
????Copyright (c) 1982?? 2013?? Oracle.  All rights reserved.
????Connected to an idle instance.
????SQL> create pfile='/u01/init.ora' from spfile;
????File created.
????[oracle@focorcl-ogg01 trace]$ vi /u01/init.ora
????--???
????*.memory_max_target=20G
????*.memory_target=20G
????[oracle@focorcl-ogg01 trace]$ sqlplus / as sysdba
????SQL*Plus: Release 11.2.0.4.0 Production on Fri Jul 8 00:01:29 2016
????Copyright (c) 1982?? 2013?? Oracle.  All rights reserved.
????Connected to an idle instance.
????SQL> create spfile from pfile='/u01/init.ora';
????File created.
????SQL> startup;
????ORACLE instance started.
????Total System Global Area 2.1379E+10 bytes
????Fixed Size          2262656 bytes
????Variable Size        1.2885E+10 bytes
????Database Buffers     8455716864 bytes
????Redo Buffers           36073472 bytes
????Database mounted.
????Database opened.
????????????