Encounter cursor: pinS wait event
Encounter cursor: pin S wait event
Background:
Master Database: Two rac nodes. Each node has eight logical CPUs and 16 GB memory.
There are dg slave machines, and the dg slave machine is a single machine: 8 logic CPUs, 16 GB memory
Due to the upgrade of the storage microcode, the primary database rac temporarily runs the db switchover to the dg backup machine for one day. During the day when the backup machine undertakes the business, there are many cursor in the v $ session: the pin S waits for the event and the front-end business feedback is slow. Well, it is not a good thing sometimes when there are too many soft resolutions.
The configuration of the dg backup machine is equivalent to one node of the rac, and the disaster recovery capability of the backup machine is obviously insufficient.
Therefore, when the storage microcode of rac is upgraded, db switchover returns to rac, and the front-end app will not respond.
It is recommended that the disaster recovery configuration be equal to the sum of the configurations of all nodes in rac.