RE: Fragmentation with restore multiple channels
Date: Tue, 4 Sep 2012 06:38:38 -0400
Message-ID: <079401cd8a89$7256b490$57041db0$_at_gmail.com>
Rman just allocates the number of datafiles by the number of datafiles so it you have 120 files and 6 channels, each channel would eventually backup 20 files so no fragmentation is possible with a full backup. With an incremental or differential backup there could be some validity in theory but I agree with Tim Gorman that it is just a tuning exercise and most likely will show another cause but only after conclusive proof would I point to RMAN as the cause.
Ken
-----Original Message-----
From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]
On Behalf Of Alex Cwb
Sent: Monday, September 03, 2012 10:35 AM
To: oracle-l_at_freelists.org
Subject: Fragmentation with restore multiple channels
Hi people,
Recently I am facing a problem with fragmentation. A supplier is arguing that the way we did a restore using RMAN with multiple channels is causing many fragmentation on the database, and consequently their application on my company is running slowly.
The restore has been done using 6 channels, and I guess that is not true. The database is being used for testing purposes only, and during this phase it's not happening updates.
Anyways, I did some research and I couldnt find a resonable answer. So I am in doubt if restore in multiple channels really causes fragmentation. Does someone have any experience on that??
Thank you for sharing.
Alex
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Received on Tue Sep 04 2012 - 05:38:38 CDT