Re: Unable to shutdown the database
Date: Sat, 03 Nov 2012 18:20:27 +1100
Message-ID: <k72gim$uk$1_at_dont-email.me>
zigzagdna_at_yahoo.com wrote,on my timestamp of 3/11/2012 3:04 PM:
> “local”; i.e., we do not use SAN in this site. Thanks a lot for your insight
> on different ways of shutting down. I have read at few places, there is
> nothing wrong with shutdown abort (other than users uncommited work will be
> interrupted) and then doing startup and then shutdown immediate . You will
> not risk your database in anyway by doing 3 steps. Instead of just one
> step shutdown immediate.
>
Shutdown normal will almost always not result in a speedy shutdown. Mostly because Oracle has to wait for all pending transactions to finish. Shutdown abort will not wait for anything and just crash the instance immediately. It's good for some of the situations I mention ahead.
Shutdown immediate will most of the time do the right thing in usable time. The
only two situations I know of where it'll be slow (aside from bugs - yes, they
happen in the best families...) are:
- when there are lots of connected sessions and they all need to be closed and
rolled back
- when large portions of memory have been swapped out, including portions of the
SGA.
The above two are not exclusive by any stretch of the imagination.
As well, it is a good practice to shutdown the listener before shutting down the
db: in very busy connect/disconnect applications the listener may indeed affect
how fast the db can come down.
One thing I've done is to use largepages for the SGA of most of my databases.
It ensures the SGA is never paged out and the only thing I have to worry about
on a shutdown is getting all the sessions closed. It takes around half a minute
for one of our dbs with 700+ connected sessions. Sometimes a bit longer if a lot
of idle sessions have been swapped out and need to be brought back in.
Received on Sat Nov 03 2012 - 08:20:27 CET