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@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Alex Cwb Sent: Monday, September 03, 2012 10:35 AM To: oracle-l@xxxxxxxxxxxxx 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 -- //www.freelists.org/webpage/oracle-l ----- Checked by AVG - www.avg.com Version: 2012.0.2197 / Virus Database: 2437/5245 - Release Date: 09/03/12 ----- Checked by AVG - www.avg.com Version: 2012.0.2197 / Virus Database: 2437/5246 - Release Date: 09/03/12 -- //www.freelists.org/webpage/oracle-l