事务回滚时间估算
事务回滚时间估算 1、当Oracle处于open 状态,当Oracle回滚事务的时候,可以从used_urec,used_ublk数值可以初步估计Oracle回滚事务的速度。 SQL> select a.sid, a.username, b.xidusn, b.us...
等待事件--db file scattered reads
等待事件--db file scattered reads Possible CausesThe Oracle session has requested and is waiting for multiple contiguous database blocks (up to DB_FILE_MULTIBLOCK_READ_COUNT) to be re...
等待事件--db file sequential reads
等待事件--db file sequential reads Possible CausesUse of an unselective index Fragmented IndexesHigh I/O on a particular disk or mount pointBad application designIndex reads performance c...
Goldengate单表添加同步
Goldengate单表添加同步 1、停止源端的pump进程stop p* 2、源端增加表附加日志dblobin userid user@orcl, password ####add trandata linfeng.tab_1 3、源端数据库获取当前最新scnse...
性能调优小记
性能调优小记 这里以Linux为例,其他操作系统可能命令稍有不同。1、查看系统资源情况vmstat命令详见Linux文档/opt/oracle>vmstat 2procs &n...