alter system set sga_max_size=960M scope=spfile;
shutdown immediate
startup

SQL> startup
ORA-00844: Parameter not taking MEMORY_TARGET into account
ORA-00851: SGA_MAX_SIZE 985661440 cannot be set to more than MEMORY_TARGET 784334848.

[oracle@wing ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Mon Feb 15 14:04:46 2016
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to an idle instance.
SQL> create pfile='/home/oracle/pfile.new' from spfile='/u01/app/oracle/product/11.2.0/db_1/dbs/spfilewingdb.ora';
File created.
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
通过vi修改pfile.new文件中相应的参数（本文档中是memory_target参数），修改后保存 
[oracle@wing ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Mon Feb 15 14:04:46 2016
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup pfile='/home/oracle/pfile.new'
ORACLE instance started.
Total System Global Area 810090496 bytes
Fixed Size     2257520 bytes
Variable Size    415239568 bytes
Database Buffers   390070272 bytes
Redo Buffers    2523136 bytes
Database mounted.
Database opened.
SQL> create spfile='/u01/app/oracle/product/11.2.0/db_1/dbsspfilewingdb.ora' from pfile='/home/oracle/pfile.new';
File created.
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@wing ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Mon Feb 15 14:08:40 2016
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to an idle instance.
SQL> 
SQL> startup
ORACLE instance started.
Total System Global Area 810090496 bytes
Fixed Size     2257520 bytes
Variable Size    415239568 bytes
Database Buffers   390070272 bytes
Redo Buffers    2523136 bytes
Database mounted.
Database opened.
SQL> show parameter memory 
NAME         TYPE
------------------------------------ --------------------------------
VALUE
------------------------------
hi_shared_memory_address    integer
0
memory_max_target     big integer
800M
memory_target      big integer
800M
shared_memory_address    integer
0
SQL> show parameter sga
NAME         TYPE
------------------------------------ --------------------------------
VALUE
------------------------------
lock_sga        boolean
FALSE
pre_page_sga       boolean
FALSE
sga_max_size       big integer
776M
sga_target       big integer
740M
# 至此Oracle使用新的spfile启动成功，参数也得到相应的修改