Re: Question on MAXDATAFILES and Control Files.

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

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"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

>