log_archive_max_processes in DG
- From: Kumar Madduri <ksmadduri@xxxxxxxxx>
- To: Oracle-L@xxxxxxxxxxxxx
- Date: Thu, 2 Jul 2009 09:21:25 -0700
Hi
I have seen several examples of Data Guard setup where
log_archive_max_processes is set at 30. But I read that setting these to
high values can cause memory issues. Oracle documentation on this parameter
also says the default of 2 should be fine for most cases. What should this
number be set when you are setting up Data Guard?
*
The LOG_ARCHIVE_MAX_PROCESSES initialization parameter specifies the number
of ARCn processes that the database initially invokes. The default is two
processes. There is usually no need specify this initialization parameter or
to change its default value, because the database starts additional archiver
processes (ARCn) as needed to ensure that the automatic processing of filled
redo log files does not fall behind.
However, to avoid any runtime overhead of invoking additional ARCn
processes, you can set the LOG_ARCHIVE_MAX_PROCESSES initialization
parameter to specify up to ten ARCn processes to be started at instance
startup. The LOG_ARCHIVE_MAX_PROCESSES parameter is dynamic, and can be
changed using the ALTER SYSTEM statement. The database must be mounted but
not open. The following statement increases (or decreases) the number of
ARCn processes currently running:
ALTER SYSTEM SET LOG_ARCHIVE_MAX_PROCESSES=3;*
Also another related question is about Standby Redo Logs. If you are
planning to set the DG in max performance mode, would there be any advantage
in adding SRL? I undertand that having SRL will give the ability to have the
lates online redo log info in SRL and decreases my recovery time. But if
that is not a criteria , would I be better off without adding SRL (From a
performancce point of view).
Thank you
- Kumar
Other related posts:
