在系统中,通过statspack得到TOP5的等待事件如下:
Avg
Total Wait waitWaits
Event
Waits Timeouts Time (s) (ms) /txn
---------------------------- ------------ ---------- ---------- ------ --------
PX Deq: Txn Recovery Start
5,2775,277 10,550 19990.2
PX Deq: Join ACK
1,9191,6363,516 18320.1
log file sync
23,3101,3852,258 971.1
log buffer space
2,0987901,0745120.1
db file parallel write
3,2821,6308542600.1
第一、二两名的等待事件,是在什么情况下产生的呢? |