Functions of affsert and NOFFRIM parameters in DataGuard

LGWR and affrem, the log writing process synchronously writes REDODATA to the DISK. before writing the DISK, the control is not handed over to the user, and the online logs of the master database may not be used before archiving.

LGWR and affrem, the log writing process synchronously writes redo data to the DISK. before writing the DISK, the control is not handed over to the user, and the online logs of the master database may not be used before archiving.

Purpose: control whether the log Transmission Service asynchronously or synchronously writes log data to the disk.

Affrem: Before the log writing process is in progress, the archive log and the backup database log must be synchronized and written.

Noffrem: the log Writing Process in the master database does not wait until all disk IO is completed.

The default value is noffrem.

Make sure that the following three points are met when you use affrem:

1. Ensure that the data is not lost after the master database fails.

2 can be used locally or remotely

3. The performance of the master database is affected.

The log writing process synchronously writes redo data to the DISK. before writing the DISK, the control is not handed over to the user, in addition, the online logs of the master database may not be used to synchronize the write redo data to the disk by ARCH and affrem ARCn processes before the archiving is completed. The Archiving operation may take a long time, online logs of the master database may be unavailable before logs are archived.

ASYNC and affrem, performance is not affected.