USN 

NUMBER 

Rollback segment number 

EXTENTS 

NUMBER 

Number of extents in rollback segment 

RSSIZE 

NUMBER 

Size in bytes of rollback segment. This values differs by the number of bytes in one database block from the value of the BYTES column of the ALL/DBA/USER_SEGMENTS views.

See Also: Oracle8i Administrator's Guide. 

WRITES 

NUMBER 

Number of bytes written to rollback segment 

XACTS 

NUMBER 

Number of active transactions 

GETS 

NUMBER 

Number of header gets 

WAITS 

NUMBER 

Number of header waits 

OPTSIZE 

NUMBER 

Optimal size of rollback segment 

HWMSIZE 

NUMBER 

High water mark of rollback segment size 

SHRINKS 

NUMBER 

Number of times the size of a rollback segment decreases 

WRAPS 

NUMBER 

Number of times rollback segment is wrapped 

EXTENDS 

NUMBER 

Number of times rollback segment size is extended 

AVESHRINK 

NUMBER 

Average shrink size 

AVEACTIVE 

NUMBER 

Current size of active extents, averaged over time. 

STATUS 

VARCHAR2(15) 

Rollback segment status 

CUREXT 

NUMBER 

Current extent 

CURBLK 

NUMBER 

Current block