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Re: Defrag tool on the Oracle database server

From: Nuno Souto <>
Date: Tue, 10 Feb 2004 21:13:56 +1100
Message-ID: <017a01c3efbe$c2504110$9b00a8c0@dcs001>

And these things, like most others in NTFS, are fully configurable. For those interested, I do recommend reading the FULL description of the "fsutil" command. New in XP, I believe it was there in W2K Pro and ES but undocumented. It allows you to trim/control/configure most of these file system parameters.

Some are VERY relevant to Oracle.

This is an interesting tech note in the M$ website:

watch out for wrapping, try this if all else fails:

And of course, don't forget:
if you REALLY want to bump up those DFMBR read sizes for FTS! This last one also has a bearing on the minimal portion/fragment that a file can be split into at create time, although I've only seen that described outside of M$ (undoco?).

Don't forget one very important thing: BY DEFAULT, NTFS is configured to provide optimal "file server" functionality. That's HEAPS of SMALL files, in the Queen's language.

Nothing could be more removed from the reality of Oracle db files: FEW, VERY LARGE files.

So, be prepared for heaps of tuning/configuring. And for Pete's sake (or any other of Pete's drinks that turn you on), do NOT create Oracle database files in anything other than a freshly formatted NTFS partition!!!!!

To their credit, M$ nowadays provides incredible amounts of doco of good to very good quality in their site. That was not always the case...

Or, take the easy way out: install 10g, give it unformatted (raw) partition(s) to manage and be done with all these problems. (and if you believe that, you're really brave...) :D

Nuno Souto
in sunny Sydney, Australia

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Received on Tue Feb 10 2004 - 04:13:56 CST

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