On Wed, Mar 31, 2010 at 4:00 AM, Simon Riggs <si...@2ndquadrant.com> wrote: > Please add some docs that a) explains what the patch does and b) notes > any changes from behaviour in previous releases. ISTM this is a major > change in behaviour.
I guess I see this a little bit differently. If you do a smart shutdown on 8.4, the autovacuum launcher won't prevent s smart shutdown from completing successfully. Neither will the background writer. If they did, we'd consider that a bug and fix it. walreceiver is just one more system process that needs to get properly shut down when a smart shutdown is requested. So I don't think this is a major behavior change - I think it's preserving the behavior we've had all along. The current documentation reads: In stop mode, the server that is running in the specified data directory is shut down. Three different shutdown methods can be selected with the -m option: "Smart" mode waits for online backup mode to finish and all the clients to disconnect. This is the default. "Fast" mode does not wait for clients to disconnect and will terminate an online backup in progress. All active transactions are rolled back and clients are forcibly disconnected, then the server is shut down. "Immediate" mode will abort all server processes without a clean shutdown. This will lead to a recovery run on restart. That all still seems accurate after this patch. I'm not even sure what to add. I suppose we could add a sentence like If a smart shutdown is requested while the server is in recovery, recovery will stop and the server will shut down. ...but if we add that then why don't we have a similar sentence that says: If a smart shutdown is requested while the autovacuum launcher is running, the autovacuum launcher will be stopped and the server will shut down. I just don't see that we're adding any additional clarity here. I think what would require documentation is if we DIDN'T apply this patch. Then we'd need something like: Smart shutdown mode should not be used if streaming replication is in use. The server will begin to shut down but, because the streaming replication process is not automatically shut down, it will never actually finish shutting down unless the streaming replication process crashes. If a server using streaming replication is accidentally shut down using smart mode, the problem can be corrected by shutting down again using fast or immediate mode. ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers