It's true that in 8i, log_cjeckpoint_timeout (for example) doesn't mean "10
seconds are up, so let's checkpoint", but "where was I ten seconds ago, I'll
checkpoint up to that point". Not sure that turns it into a dribbler,
though... fast_start_io_target does that, for sure.
Regards
HJR
--
----------------------------------------------
Resources for Oracle: http://www.hjrdba.com
===============================
"Connor McDonald" <connor_mcdonald_at_yahoo.com> wrote in message
news:3C7D5C53.4458_at_yahoo.com...
> Keith Boulton wrote:
> >
> > Keith Boulton <kboulton_at_ntlworld.com> wrote in message
> > news:V24e8.28567$hM6.3678545_at_news6-win.server.ntlworld.com...
> > > failure than in the last 2 hours, so I would go for a checkpoint
timeout
> > in
> > > that case.
> > >
> > Doh!
> >
> > Of course, as someone else pointed out, checkpoint timeout is irrelevant
to
> > this discussion.
> >
> > I do, however, have a question.
> >
> > Has anyone actually tested the impact of these parameters on recovery
time?
> >
> > As I said, I have in the past attempted to find a penalty associated
with
> > larger logs, but always with checkpoint interval set high and checkpoint
> > timeout set to 0. While I'm happy enough to believe that my testing
matches
> > by theorising about limiting factors affecting restart time, I can't
help
> > wondering if there's something I've missed.
> >
> > Any suggestions?
>
> I'm coming in late to this to thread so apologies if someone has already
> posted this detail. From 8.1 onwards, both the 'log_chec...' parms no
> longer work in a "oh-i-have-expired,do-a-checkpoint" fashion. All they
> do is ensure that buffers don't that much out of date, so you get data
> "dribbling" continuously out to the datafiles
>
> hth
> connor
> --
> ==============================
> Connor McDonald
>
> http://www.oracledba.co.uk
>
> "Some days you're the pigeon, some days you're the statue..."
Received on Wed Feb 27 2002 - 18:18:02 CST
