RMAN 10gR2 Tape vs Disk Backup Performance When Database is 99% Empty (Doc ID 428344.1)

Last updated on OCTOBER 12, 2016

Applies to:

Oracle Server - Enterprise Edition - Version 10.2.0.2 and later
Information in this document applies to any platform.

Symptoms

Full database backup is running extremely slowly: rate of transfer to tape is approximately
200K/second.
If they take a single large 100Gb tablespaceand issue backup validate to tape and then to disk
then the following times are noted:

backup validate to tape: 601 secs
backup validate to disk: 5 secs

Using RMAN debug trace we can see for disk backups:

"krbbnbf - Using Unused Block Compression algorithm to speed up backup"

And for tape backups:

"krbbSetOutputDevice: Unused Block Compression disabled due to channel type"




.

Cause

Sign In with your My Oracle Support account

Don't have a My Oracle Support account? Click to get started

My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms