Oracle ADG AFFIRM/NOAFFIRM VS SYNC/ASYNC

Oracle ADG Affirm VS SYNC

 

SYNC and ASYNC

Specifies that network I/O is to be done synchronously (SYNC) or asynchronously (ASYNC) when archival is performed using the log writer process (LGWR).

 

Note:

When the primary database is in maximum protection mode or maximum availability mode, destinations archiving to standby redo log files and using the log writer process are automatically placed in SYNC mode.

Category	SYNC	ASYNC
Data type	Keyword	Numeric
Valid values	Not applicable	Not applicable
Default value	Not applicable	None
Requires attributes ...	None	LGWR
Conflicts with attributes ...	ASYNC	SYNC, LOCATION, ARCH
Corresponds to ...	TRANSMIT_MODE column of the V$ARCHIVE_DEST view	TRANSMIT_MODE and ASYNC_BLOCKS columns of the V$ARCHIVE_DEST view

Usage Notes

 

 

 

Table 5-2 Minimum Requirements for Data Protection Modes

	Maximum Protection	Maximum Availability	Maximum Performance
Redo archival process	LGWR	LGWR	LGWR or ARCH
Network transmission mode	SYNC	SYNC	SYNC or ASYNC when using LGWR process. SYNC if using ARCH process
Disk write option	AFFIRM	AFFIRM	AFFIRM or NOAFFIRM
Standby redo log required?	Yes	Yes	No, but it is recommended