SQL> col comments format a80
SQL> select table_name, comments from dict where lower(comments) like '%storage%' order by 1;
TABLE_NAME                     COMMENTS
------------------------------ --------------------------------------------------------------------------------
DBA_RSRC_STORAGE_POOL_MAPPING  resource manager rules for mapping files to storage pools
DBA_SEGMENTS                   Storage allocated for all database segments
DBA_SEGMENTS_OLD               Storage allocated for all database segments
USER_SEGMENTS                  Storage allocated for all database segments

Tablespace      Used MB.       Free MB. Total MB %Free
RDSADMIN	0	       7	7	100
UNDO_T1	        60	       780	840	93
USERS	        139	       3997	4136	97
SYSTEM	        507	       93	600	16
SYSAUX	        8008	       483	8491	6

Server Manageability - Advisor Framework	6657.1875
Server Manageability - Optimizer Statistics History	688.5625
Server Manageability - Automatic Workload Repository	335.375
Unified Job Scheduler	79.75
Server Manageability - Other Components	63
XDB	62.25
LogMiner	14.625
Oracle Text	4.125
Transaction Layer - SCN to TIME mapping	3.25
SQL Management Base Schema	2.4375
PL/SQL Identifier Collection	2.375
Analytical Workspace Object Table	1.9375
OLAP API History Tables	1.9375
Logical Standby	1.5
Oracle Streams	1.1875
Enterprise Manager Monitoring User	0.9375
AUDSYS schema objects	0.625
Automated Maintenance Tasks	0.3125

select occupant_desc, space_usage_kbytes/1024 MB
from v$sysaux_occupants
where space_usage_kbytes > 0
order by space_usage_kbytes;