RE: Restore/Duplicate takes a lot longer to restore than backup

From: Taylor, Chris David <>
Date: Wed, 6 Jan 2010 13:40:28 -0600
Message-ID: <>

Well, a restore/duplicate recreates the datafiles (and their sizes) so a big component of the time required is writing the new datafiles. So, lets say you have multiple datafiles that are several gigabytes in size, they take a bit of time to write out. In a backup, you're only reading blocks of data out of datafiles and backing up those blocks. Right?
Chris Taylor
Sr. Oracle DBA
Ingram Barge Company
Nashville, TN 37205
Office: 615-517-3355
Cell: 615-354-4799

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Subject: Restore/Duplicate takes a lot longer to restore than backup

We are doing a compressed backup of a 200G database in about 2 hours. When we run the duplicate command, we copy the production backup files to the local disks of the target server. We then run the RMAN duplicate command and it takes over 6 hours. Is it reasonable that a restore/duplicate from a compressed backup takes that much longer than the actual backup? Is there anything that can be done to speed up the process?

Jeffrey Beckstrom
Database Administrator
Greater Cleveland Regional Transit Authority 1240 W. 6th Street
Cleveland, Ohio 44113

Received on Wed Jan 06 2010 - 13:40:28 CST

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