C:\Users\Administrator>sqlplus /nolog

SQL*Plus: Release 10.2.0.4.0 - Production on Wed Jan 8 16:44:13 2014

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SQL> conn / as sysdba
Connected.
SQL> alter system set archive_lag_target=10;

System altered.

SQL> archive log list
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     13
Next log sequence to archive   15
Current log sequence           15

查询v$log,v$archive_log会发现redo log 在指定时间内必须归档

SQL> select to_char(completion_time,'yyyy-dd-mm hh24:mi:ss') from v$archived_log;

TO_CHAR(COMPLETION_
-------------------
2014-08-01 16:38:29
2014-08-01 16:39:30
2014-08-01 16:40:33
2014-08-01 16:41:37
2014-08-01 16:42:41
2014-08-01 16:43:44
2014-08-01 16:44:51
2014-08-01 16:45:57
2014-08-01 16:47:04

9 rows selected.

  查询归档完成时间都非常短。