Wed Feb 01 15:42:14 2012

Thread 1 cannot allocate new log, sequence 207602

Checkpoint not complete

  Current log# 1 seq# 207601 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO01.LOG

Thread 1 advanced to log sequence 207602 (LGWR switch)

  Current log# 2 seq# 207602 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO02.LOG

Thread 1 cannot allocate new log, sequence 207603

Checkpoint not complete

  Current log# 2 seq# 207602 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO02.LOG

Thread 1 advanced to log sequence 207603 (LGWR switch)

  Current log# 3 seq# 207603 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO03.LOG

Wed Feb 01 15:42:29 2012

Thread 1 cannot allocate new log, sequence 207604

Checkpoint not complete

  Current log# 3 seq# 207603 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO03.LOG

Thread 1 advanced to log sequence 207604 (LGWR switch)

  Current log# 1 seq# 207604 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO01.LOG

Thread 1 cannot allocate new log, sequence 207605

Checkpoint not complete

  Current log# 1 seq# 207604 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO01.LOG

Thread 1 advanced to log sequence 207605 (LGWR switch)

  Current log# 2 seq# 207605 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO02.LOG

Thread 1 cannot allocate new log, sequence 207606

Checkpoint not complete

  Current log# 2 seq# 207605 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO02.LOG

Thread 1 advanced to log sequence 207606 (LGWR switch)

  Current log# 3 seq# 207606 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO03.LOG

Wed Feb 01 15:42:59 2012

Thread 1 cannot allocate new log, sequence 207607

Checkpoint not complete

  Current log# 3 seq# 207606 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO03.LOG

Thread 1 advanced to log sequence 207607 (LGWR switch)

  Current log# 1 seq# 207607 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO01.LOG

Wed Feb 01 15:45:42 2012

Thread 1 cannot allocate new log, sequence 207608

Checkpoint not complete

原来出现这个问题的频率是每分钟都有，

Wed Feb 01 18:43:16 2012

Thread 1 cannot allocate new log, sequence 207618

Private strand flush not complete

  Current log# 1 seq# 207617 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO001.LOG

Thread 1 advanced to log sequence 207618 (LGWR switch)

  Current log# 2 seq# 207618 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO002.LOG

Wed Feb 01 19:38:01 2012

Thread 1 advanced to log sequence 207619 (LGWR switch)

  Current log# 3 seq# 207619 mem# 0: D:\ORACLE\ORADATA\NODMDB\REDO003.LOG

Wed Feb 01 19:47:06 2012

Thread 1 advanced to log sequence 207620 (LGWR switch)

  Current log# 4 seq# 207620 mem# 0: E:\ORACLELOG\REDOLOG004.LOG

Wed Feb 01 20:43:52 2012

Thread 1 cannot allocate new log, sequence 207621

Private strand flush not complete

  Current log# 4 seq# 207620 mem# 0: E:\ORACLELOG\REDOLOG004.LOG

Thread 1 advanced to log sequence 207621 (LGWR switch)

  Current log# 5 seq# 207621 mem# 0: E:\ORACLELOG\REDOLOG005.LOG

经过昨天的更改之后，大概两个小时出现了一次。

把db_writer_processes从2加大到4，希望能解决上面出现的问题，但这个修改要数据库重启才会起作用的。

参考：http://blog.csdn.net/tianlesoftware/article/details/6015400

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