Re: Question on MAXDATAFILES and Control Files.

Howard,

there's more to it than just that. Some buffers seem to depend on it. Can't recall where I read that, tho (ixora?). However, implications were such that I decided to keep it "reasonable", e.g. allow a factor 10 slack. The 3000 vs 30 you mention would not fall in that category.

"Howard J. Rogers" wrote:

> For maxdatafiles, every extra file you specify takes an addition 180 bytes
> in the Control File. So the difference between a maxdatafiles of 30 (the
> default!!!!!!) and 3000 is 180000 bytes -or 180K. Anyone who can't afford
> an additional 180K of disk space wants to quit the Oracle game immediately.
>
> Set 'em big and forget about 'em!
>
> Incidentally, query v$control_file_record_section (or something very
> similarly-named!) and you can see what the max setting is for each
> parameter, what you are currently using, and the number of bytes per file
> pointer.
>
> A fellow-instructor told me two weeks ago that db_files in the init.ora
> actually dynamically overcomes the limitations of a too-low maxdatafiles
> setting, so that you don't have to re-create the controlfile if you hit the
> limit. Magic if so, but I remain sceptical. Put it this way, I haven't
> gone to the effort of testing it!
>
> Regards
> HJR
> --
> --------------------------------------------------------------------------
> Opinions expressed are my own, and not those of Oracle Corporation
> Oracle DBA Resources: http://www.geocities.com/howardjr2000
> --------------------------------------------------------------------------
>
> "William Dieterich" <wdieteri_at_rmi.net> wrote in message
> news:39FD04A7.C7955724_at_rmi.net...
> > I have been doing some reading and research into the MAXDATAFILES and
> > db_files parameters. The only reason that Oracle gives for not setting
> > the MAXDATAFILES to the max allowed by Operating system and database
> > version are that they increase the size of the control files.
> >
> > First off lets say that the size of the control files really matters, on
> > my 10 Gig database their size was insignificant. Has anyone done any
> > experiments to see how much setting them to system max from a reasonable
> > number does affect size? Beside control file size has anyone discovered
> > any other reason?
> >
> >
> > Thanks
> >

--
Gtrz,

Frank van Bortel