From: Frank Hubeny <fhubeny@ntsource.com>
Newsgroups: comp.databases.oracle.server
Subject: Re: 2gb filesize, large disks and splitting tablespaces
Date: Tue, 05 Jun 2001 23:33:26 -0700
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I once inherited a running database where the tablespaces where created with the
datafiles sized at precisely 2GB ("size 2048m").  The question arose whether we
should risk using "large files".  Were they safe?  However, when we looked at
the size of the database files currently being used, we were surprised to find
that they were already well over 2 gigabytes.  Apparently there was additional
header information that made these files larger than expected not to mention the
fact that they were declared to be over the 2 gigabyte limit by 1 byte.

Encouraged by the fact that the sky had not fallen on this database, we let the
files get even larger.

The sky still did not fall.

Frank Hubeny

andrew_webby at hotmail wrote:

> A post I just saw of Niall's reminded me of something. I'm on
> Solaris7/Oracle 816 (Sparc) and remember the dire warnings in days of yore
> about unix 'largefiles', ie. files over 2gb in size.
>
> ps. Volume Manager 3.0.4, VXFS 3.3.2
>
> I know Solaris7 has support for them, and I (think I) know Oracle is fine
> with it, but in this combination? Yay? Nay? Eh? Horror stories? Success?
>
> In fact, what is the current thinking these days regarding large disks?
> Reason I ask is at the moment, the array is populated with 4gb disks (!),
> but the new array coming is 18gb disks.
>
> As an *example*: suppose I have an 18gb disk and at the moment, I have 3x2gb
> files making a 6gb tablespace. Assuming *just for the sake of argument* I
> had to put these on the one disk, would you still place them in 3 files on
> that disk or in one file?
>
> Any advantages one way or the other d'ya think? Such a thing as 'datafile
> header contention'? Are the db_writer's more 'intelligent' with multiple
> files?
>
> Discuss....
>
> Andrew :o)


