Performance Tuning - Question 035

Which events trigger the log writer process, LGWR, to begin writing from the redo log buffer to the online redo log file or to members of the active redo log group? (Choose three.)

A. A server process performs a COMMIT or ROLLBACK.

B . The redo log file becomes one-third full.

C. A DBWn process tells LGWR to write.

D. The log buffer becomes one-third full.

E . The server process tells ARCH to write.

Explanation:

Answer A, C and D: By definition, these are the events that trigger LGWR to write all the log buffer entries to the redo log file or files. The server processes do not tell ARCH to write to the redo logs; ARCH is responsible for writing to the archived redo logs.