Purpose
One of the features of ASM is databases consolidation. A single diskgroup will be the repository for multiple databases. The result, having a large number of datafiles. If the files were created using OMF (Oracle Managed Files) format, when the datafile is deleted on the database side, it is also deleted on the ASM side. There may be situations when the datafiles are not deleted on the ASM side, particularly when not using OMF format.
With large diskgroups holding large number of datafiles it is necessary to make good usage of the storage and reclaim space allocated for files not used by the databases.
The following script will provide the list of files stored in ASM and CURRENTLY NOT OPENED by any database client of the diskgroups. It is very important to validate the results of the query, particularly for files that could have been marked temporary offline. It does not apply to READ ONLY tablespaces, because once the file is opened by the database, it will be returned by the query.
Pre-requisites
– The query has to be executed on the ASM instance.
– Diskgroups need to be mounted.
The script
The script can be run on the ASM instance as shown below:
$ sqlplus '/ as sysdba' sql>@files_not_opened
The script is given below:
set pagesize 0
set linesize 200
col full_alias_path format a80
/*+ ----------------------------------------------------------------
Query will return all the files stored on ASM but not currenlty
opened by any database client of the diskgroups
ordered by group number, file type
---------------------------------------------------------------*/
select * from (
/*+ -----------------------------------------------------------------
1st branch returns all the files stored on ASM
-----------------------------------------------------------------*/
select x.gnum,x.filnum,x.full_alias_path,f.ftype from (
SELECT gnum,filnum,concat('+'||gname, sys_connect_by_path(aname, '/')) full_alias_path
FROM (SELECT g.name gname, a.parent_index pindex, a.name aname,
a.reference_index rindex,a.group_number gnum,a.file_number filnum
FROM v$asm_alias a, v$asm_diskgroup g
WHERE a.group_number = g.group_number)
START WITH (mod(pindex, power(2, 24))) = 0 CONNECT BY PRIOR rindex = pindex) x,
(select group_number gnum,file_number filnum, type ftype from v$asm_file order by group_number,file_number) f
where x.filnum != 4294967295
and x.gnum=f.gnum and x.filnum=f.filnum
MINUS
/*+ --------------------------------------------------------------
2nd branch returns all the files stored on ASM
and currently opened by any database client of the diskgroups
-----------------------------------------------------------------*/
select x.gnum,x.filnum,x.full_alias_path,f.ftype
from ( select id1 gnum,id2 filnum from v$lock where type='FA' and (lmode=4 or lmode=2)) l,
(
SELECT gnum,filnum,concat('+'||gname, sys_connect_by_path(aname, '/')) full_alias_path
FROM (SELECT g.name gname, a.parent_index pindex, a.name aname,
a.reference_index rindex,a.group_number gnum,a.file_number filnum
FROM v$asm_alias a, v$asm_diskgroup g
WHERE a.group_number = g.group_number)
START WITH (mod(pindex, power(2, 24))) = 0 CONNECT BY PRIOR rindex = pindex
) x,
(select group_number gnum,file_number filnum, type ftype from v$asm_file order by group_number,file_number) f
where x.filnum != 4294967295 and
x.gnum=l.gnum
and x.filnum=l.filnum
and x.gnum=f.gnum and x.filnum=f.filnum) q
order by q.gnum,q.ftype
;
Sample output
This is the first example of the results of the execution of the script. Note that it includes all type of files like ARCHIVELOGS, FLASHBACK LOGS, REDOLOGS. Once it has been confirmed the files are not required any more, then they can be deleted using ASMCMD or SQL running the command ALTER DISKGROUP … DROP FILE ‘[path]’;
GNUM FILNUM FULL_ALIAS_PATH
---------- ---------- ----------------------------------------------------------------------
1 270 +DATA1/G102/ONLINELOG/group_2.270.645209903
1 3247 +DATA1/G102/ARCHIVELOG/2008_01_30/thread_2_seq_54.3247.645369463
1 3249 +DATA1/G102/ARCHIVELOG/2008_01_30/thread_1_seq_59.3249.645367259
1 3250 +DATA1/G102/FLASHBACK/log_104.3250.645367249
1 3251 +DATA1/G102/FLASHBACK/log_103.3251.645369221
1 3252 +DATA1/G102/ARCHIVELOG/2008_01_30/thread_1_seq_58.3252.645367197
1 3254 +DATA1/G102/ARCHIVELOG/2008_01_30/thread_2_seq_53.3254.645369095
1 3255 +DATA1/G102/ARCHIVELOG/2008_01_30/thread_1_seq_57.3255.645366969
1 3256 +DATA1/G102/ARCHIVELOG/2008_01_30/thread_2_seq_52.3256.645368439
1 3257 +DATA1/G102/ARCHIVELOG/2008_02_04/thread_2_seq_59.3257.645786351
1 3258 +DATA1/G102/FLASHBACK/log_13.3258.645786863
As mentioned before, it is extremely important to review the results of the script. In this following example, these datafiles are not currently opened but they belong to a database currently closed.
GNUM FILNUM FULL_ALIAS_PATH
---------- ---------- ----------------------------------------------------------------------
2 256 +DG_NETAPPS/V102/DATAFILE/UNDOTBS2.256.643467013
2 257 +DG_NETAPPS/NETAPP/DATAFILE/SYSTEM.257.643477635
2 258 +DG_NETAPPS/NETAPP/DATAFILE/SYSAUX.258.643477637
2 259 +DG_NETAPPS/NETAPP/DATAFILE/UNDOTBS1.259.643477641
2 260 +DG_NETAPPS/NETAPP/DATAFILE/USERS.260.643477643
2 261 +DG_NETAPPS/NETAPP/CONTROLFILE/Current.261.643478451
2 262 +DG_NETAPPS/NETAPP/ONLINELOG/group_1.262.643478461
2 263 +DG_NETAPPS/NETAPP/ONLINELOG/group_2.263.643478517
2 264 +DG_NETAPPS/NETAPP/ONLINELOG/group_3.264.643478569
2 265 +DG_NETAPPS/NETAPP/TEMPFILE/TEMP.265.643478655
2 266 +DG_NETAPPS/NETAPP/PARAMETERFILE/spfile.266.643478737
2 266 +DG_NETAPPS/NETAPP/spfilenetapp.ora
2 267 +DG_NETAPPS/NETTEST/DATAFILE/UNDOTBS1.267.643723749