RE: "Headroom" in datafiles?

From: Goulet, Richard <>
Date: Wed, 16 Sep 2009 11:40:34 -0400
Message-ID: <>


    I have a touch of a problem with that. Assuming your using an 8K block size a data file is limited to 32GB and a bigfile tablespace is limited to one datafile. What do you do when the tablespace needs to grow beyond 32GB?  

Dick Goulet
Senior Oracle DBA/NA Team Lead
PAREXEL International  

[] On Behalf Of Bobak, Mark
Sent: Wednesday, September 16, 2009 11:35 AM To:; '' Subject: RE: "Headroom" in datafiles?

Hi Chris,  

Personally, I'm a big advocate of ASM and bigfile tablespaces. I put all my storage under ASM control, and when I create a database, I make sure all tablespaces are created as bigfile tablespaces. Tablespaces like SYSTEM, SYSAUX, TEMP, I usually set a reasonable max size. My application tablespaces are unlimited, and then I just monitor the amount of free space available in the diskgroup. When space is low, talk to storage admin, he gives me another chunk of raw disk, I add it to my diskgroup, and that's it. Each tablespace grows to the size it needs to be, I don't need to monitor individual databases/tablespaces, and life is simple.  


[] On Behalf Of Taylor, Chris David
Sent: Wednesday, September 16, 2009 11:27 AM To: ''
Subject: "Headroom" in datafiles?  

I'm curious how much "headroom" people like to maintain in their datafiles? We have a large data reorganization procedure underway as part of our DR discovery process and I was playing around with some ideas.  

I was thinking, we could allocate a fixed size for each datafile (say 32G for example) and not worry about space or autoextend until we reached some threshold.


I could fix each datafile to have 10% free space at all times


something similar.  

I think what bothers me is knowing that some of my datafiles are "99%" full for example while others are 5% full in the same database.  

Do any of you get bothered by datafiles being a certain % "full"?  

We've got gobs of disk space "right now" so I've been pushing this to the back burner for a while for coming up with a cohesive policy on datafiles.  


Chris Taylor

Sr. Oracle DBA

Ingram Barge Company

Nashville, TN 37205

Office: 615-517-3355

Cell: 615-354-4799


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Received on Wed Sep 16 2009 - 10:40:34 CDT

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