磁盘慢，数据库启动失败：
解决思路：1.让数据文件offline；
2.删除表空间
SQL> startup pfile='/server/oracle/admin/test/pfile/inittest.ora'
ORACLE instance started.
Total System Global Area 776646656 bytes
Fixed Size 2217384 bytes
Variable Size 583010904 bytes
Database Buffers 188743680 bytes
Redo Buffers 2674688 bytes
Database mounted.
ORA-03113: end-of-file on communication channel
Process ID: 3466
Session ID: 1 Serial number: 5
SQL> startup mount
ORA-24324: service handle not initialized
ORA-01041: internal error. hostdef extension doesn't exist
SQL> quit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@node2 trace]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.1.0 Production on Sun Oct 21 18:53:47 2018
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup mount
ORACLE instance started.
Total System Global Area 776646656 bytes
Fixed Size 2217384 bytes
Variable Size 583010904 bytes
Database Buffers 188743680 bytes
Redo Buffers 2674688 bytes
Database mounted.
SQL> drop tablespace beijing including contents and datafiles;
drop tablespace beijing including contents and datafiles;
SQL> alter database datafile '/server/oradata/test/beijing.dbf' offline drop;
Database altered.
SQL> alter database open;
Database altered.
drop tablespace BEIJING_SPACE including contents and datafiles;