一些转储和清除内存对象和物理对象的命令

9i清buffer cache
alter session set events 'immediate trace name flush_cache level 1';

alter session set events = 'immediate trace name flush_cache';

10g中清buffer cache
alter system flush buffer_cache;

清shared pool

alter system flush shared_pool;

转储sga

alter session set events 'immediate trace name heapdump level 2';

转储library cache

ALTER SESSION SET EVENTS 'immediate trace name LIBRARY_CACHE level n';

Level =1 ,转储Library cache统计信息
Level =2 ,转储hash table概要
Level =4 ,转储Library cache对象，只包含基本信息
Level =8 ,转储Library cache对象，包含详细信息(包括child references,pin waiters等)
Level =16,增加heap sizes信息
Level =32,增加heap信息

转储控制文件、日志文件、数据文件：

alter session set events 'immediate trace name controlf level 10';
alter session set events 'immediate trace name redohdr level 3';

alter system dump logfile '...redo01.log';

alter session set events 'immediate trace name file_hdrs level 10';
ALTER SYSTEM DUMP LOGFILE '/opt/oracle9/oradata/testora9/redo01.log';
alter system dump datafile 3 block max 2 block min 4;

转储系统状态

ALTER SESSION SET EVENTS 'IMMEDIATE TRACE NAME SYSTEMSTATE LEVEL 10';