Oracle RAC 11.2 with asm storage, all type = EXTERN redundancy.
I've been cleaning up some tablespaces and shrinking datafiles back down to sizes that they're not likely to grow much larger than (processes no longer used had blown them up).
The sum of the bytes of datafiles from dba_data_files reflects this shrink, however, USED_MB in v$asm_diskgroup has not fallen and it doesn't match to what adding up the datafiles bytes is?
What would account for this difference? We typically use v$asm_diskgroup to monitor if we're running low on space but this doesn't appear to be correct.
SELECT name group_name ,
type type ,
total_mb total_mb ,
(total_mb - free_mb) used_mb ,
ROUND(
(SELECT SUM(bytes)/1024/1024
FROM dba_data_files
WHERE file_name LIKE '+DATA02%'
),0) AS datafile_used
FROM v$asm_diskgroup w
WHERE name = 'DATA02'
GROUP_NAME TYPE TOTAL_MB USED_MB DATAFILE_USED
______________________________________
DATA02 EXTERN 542712 516902 506447
Best Answer
dba_data_files
does not include:Include
v$asm_alias
andv$asm_file
in your queries, or just simply list the files in the diskgroup (asmcmd
,ls
).