ITPub博客

SQL> l  1* select name, parameter1, parameter2, parameter3 from v$event_name where name like '&event'SQL> /Enter value for event: enq: SQ - contentionold   1: select name, parameter1, parameter2, parameter3 from v$event_name where name like '&event'new   1: select name,...

SQL> l  1* select name, parameter1, parameter2, parameter3 from v$event_name where name like '&event'SQL> /Enter value for event: enq: RO - fast object reuseold   1: select name, parameter1, parameter2, parameter3 from v$event_name where name like '&event'new   1: selec...

SQL> select name, parameter1, parameter2, parameter3 from v$event_name where name like '&event'; Enter value for event: enq: HW - contentionold   1: select name, parameter1, parameter2, parameter3 from v$event_name where name like '&event'new   1: select name, parameter1, para...

Pin S wait on X is usually due to high parses.  So check for high parsing sqls or tune application to share cursors.  For further diagnosis, please review following note ：Note:1349387.1  Trouble shooting 'Cursor: Pin S wait on X' wait通常是由于高分析。 所以检查高解析sqls或调整应用程...

Troubleshooting Steps：故障排除步骤"latch: cache buffers chains" contention is typically encountered because SQL statements read more buffers than they need to and multiple sessions are waiting to read the same block.通常会遇到"latch：cache buffers chains"争用，因为SQL语句读取的缓冲区比他们需...

http://blog.csdn.net/robinson1988/article/details/5982996

事件背景：   一个客户的数据库发生了宕机事件，查看了数据库的awr报告，原来是由于出现大量的latch: cache buffers chains等待事件导致系统消耗量大量的CPU，最终导致系统hang住；说明：   要理解latch: cache buffers chains并解决这个问题，就需要深入的了解Buffer Cache及其原理。1、Buffer Cache...