resetlogs开库遇到enq:DM-contention等待事件
最近遇到案例，10.2.0.5.12下的db, alter database open resetlogs 命令一直等待，alert_sid.log 的信息为： setting recovery target incarnation to 2 从v$session.event 得到的等待事件为enq: DM - contention 从 select KSQSTTYP,KSQSTEXPL from x$ksqst
最近遇到案例，10.2.0.5.12下的db, alter database open resetlogs 命令一直等待，alert_sid.log 的信息为：
setting recovery target incarnation to 2
从v$session.event 得到的等待事件为enq: DM - contention
从 select KSQSTTYP,KSQSTEXPL from x$ksqst where KSQSTTYP='DM' 可以看到 对该等待事件的解释为：
Enqueue held by foreground or DBWR to syncrhonize database mount/open 【本文来自鸿网互联 (http://www.68idc.cn)】with other operations
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