One of my RMAN backup generated below Warnings, here is the detailed description and solution. I hope it helps other users.
RMAN-06900: WARNING: unable to generate V$RMAN_STATUS or V$RMAN_OUTPUT row
RMAN-06901: WARNING: disabling update of the V$RMAN_STATUS and V$RMAN_OUTPUT rows
ORACLE error from target database:
ORA-00604: error occurred at recursive SQL level 3
ORA-04031: unable to allocate 4120 bytes of shared memory ("shared pool","select name,password,datats#...","Typecheck","kgghteInit")
ORA-06508: PL/SQL: could not find program unit being called: "SYS.DBMS_BACKUP_RESTORE"
Cause & Solution:
The RMAN not able to update V$RMAN_STATUS or V$RMAN_OUTPUT due to associated error message. When you receive RMAN-06900 and RMAN-06901error, you need to look for associated error messages to find the root cause of the error message.
In this case, ORA-04031 is the associated error message
ORA-04031: unable to allocate 4120 bytes of shared memory
*Cause: More shared memory is needed than was allocated in the shared pool.
*Action: If the shared pool is out of memory, either use the dbms_shared_pool package to pin large packages, reduce your use of shared memory, or increase the amount of available shared memory by increasing the value of the INIT.ORA parameters "shared_pool_reserved_size" and “shared_pool_size". If the large pool is out of memory, increase the INIT.ORA parameter "large_pool_size".
I have seen many users complaining about error ORA-19921. If you receive this error close some of existing connections or unused RMAN connections.
If your oracle version > 10.2.0.4 then you might be hitting below bugs. These bugs fixed in 10.2.0.4 and higher versions.
ORA-19921: maximum number of 64 rows exceeded - oracle Bug 465973.
ORA-19921: maximum number of 128 rows exceeded - oracle Bug 8264365