Re: RMAN Performance Maladies

From: Don Seiler <don_at_seiler.us>
Date: Tue, 13 Feb 2007 15:37:37 -0600
Message-ID: <716f7a630702131337m72457875tf8118f0e23211384@mail.gmail.com>

On 2/13/07, Michael Fontana <MFontana_at_verio.net> wrote:
> Jared hit on something that will cause me to do some more testing - and that
> is that whilst sqlbacktrack merely backs up the datafiles to disk (a
> file-based backup), rman is checking blocks, etc.

This was something that bit me when I made the switch from manual hot backups to RMAN. My manual hot backup script would put a tablespace into BACKUP mode, then copy and compress each datafile in that tablespace to another slab of disk. I could backup our entire database (~800 gb) in 2-3 hours.

With RMAN, a level 0 backup takes almost 9 hours, as does a restore/duplication. Level 1 backups took around 5 hours, but once I turned on block change tracking, that dropped down to 30-45 minutes.

Don.
http://seilerwerks.blogspot.com

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Received on Tue Feb 13 2007 - 15:37:37 CST