Netbackup 7.5 very slow writting on tape with RMAN

[Nachox]

I have a problem with my RMAN backup on Netbackup 7.5.

I'm using RMAN script for backup, it was working ok until we made a DB upgrade, from Oracle 9 to 10. After the upgrade, the RMAN backup job runs at 2500kb/s, when the standard backup on the same server runs at more than 90mb/s.

The same server works as Oracle DB server and Netbackup master, media and client, and the library is conected directly via FC. The OS is RHEL 5.7.

Any ideas why the write speed is so low with RMAN?

Thanks

[Will_Restore]

If I were a betting man, I'd same something in Oracle configuration. If you are comfortable with Oracle, you can try out the scripts mentioned in this technote, or pass this info on to your DBA. 

Article URL http://www.symantec.com/docs/HOWTO31259

[revarooo]

Agreed, one other note, you should never have a Master server running with other resource hungry applications like Oracle. It would've been better having the Oracle server as a SAN Media server (server that only backs itself up) and have the Master dedicated on it's own server.

[Marianne]

I agree with Revaroo - never a good idea to run two database applications on the same server.

You may want to search Oracle web site for 'Rman Performance Tuning'. I found a couple of good articles not so long ago - will find the URLs later in the day and update this post.

[Nachox · Accepted solution]

Ok, its solved. The problem was the RMAN compression, without the compression set the writting speed is above 100mb/s. It looks like the default configuration with the db upgrade has it active, now is running ok.

I'm expecting to change the master server to a new dedicated server, this is just a temporary scenario.

Thanks everyone for your help!