Hello All,
I need help in understanding critical functionality of COMMIT statement.
As per my knowledge after a commit is issues below things takes place:
1. Transaction table is modified and a SCN number generated is marked to the UNDO record.
2. LGWR writes the redo log buffer entries to redo log files.
3. LGWR post the confirmation to server process -- prompt reture to the user.
4. Locks release,etc...
Now here in my case what i see is a COMMIT statment (RAC) is waiting for "gc current grant 2-way" as per TKPROF/TRACE
wait event gc current grant 2-way is associated with the Data Blocks that are not present on the SGA for any node and hence it has to be get from remote node,
but the doubt here is why and which blocks a COMMIT statment is expecting from remote node...