rman backup hang

[kris123]

Hi Friends,

I've just seen weird things about my rman backup to disk.
I run rman backup on 8i AIX 4.3.3. but I forgot to set the output format to direct it to a bigger disk space which is in /u04. Instead it defaulted to /u01/app/oracle/product/8.1.7/dbs. So I aborted the process immediately. When I ls -l the size of the output, i was surprised that it is 16Gb+ but my /u01 disk has onlly 2gb freespace.
It seems that it is taking a virtual space from somewhere? Is this normal about rman backups? Can I delete the output or do i have to
run some rman cleanup commands whenever I aborted an rman process.

I rerun the process again using the right output disk and i check
the outfile size and they have same size with the first aborted one.
But the process is taking so long. I wonder if it got locked up with
the aborted 1st run.


Thanks a lot for ur unfailing support

[nagarjuna]

Never seen such situation before. But, I would dig into this issue using wait events. Get SID for the processes like %rman%' and check wait events.

[kris123]

Thanks hun,

I just thought RMAN output would be a compressed one like export.
I get 2.5gb when i exported the whole db. but rman got 15gb.
does it copy the whole file systems? how about large temp and rbs
tablespaces that doesnt have data contents or data tablespaces that
have few or no tables yet.

[marist89]

Originally posted by kris123

I just thought RMAN output would be a compressed one like export.
I get 2.5gb when i exported the whole db. but rman got 15gb.

of course. rman is a backup. it includes data, indexes, free space, etc. exp is a dump of your data only.

does it copy the whole file systems?

yes

how about large temp and rbs
tablespaces that doesnt have data contents or data tablespaces that
have few or no tables yet.

temp, maybe yes maybe no. depends on how you have created it.

rbs, absolutely. This is crucial for a valid recovery.

empty tablespaces, maybe yes maybe no. rman doesn't backup blocks that were never used, but does backup blocks that were used at one time but are empty now.

[kris123]

Thanks genius

Our undo and temp tablespace sometimes grow up to 10gb each,
Im thinking it might be a good practice to shrink thier sizes to si 500mb before starting RMAN backup.

[davey23uk]

or just excluse it from the backup, dont need it for recovery

[marist89]

Originally posted by davey23uk
or just excluse it from the backup, dont need it for recovery

You don't need undo for recovery?

[davey23uk]

meant temp, didnt see undo in there

[DaPi]

Originally posted by kris123
does it copy the whole file systems?

I thought not . . . blocks that have never been occupied are not backed up.