{"id":4670,"date":"2021-11-04T16:06:19","date_gmt":"2021-11-04T07:06:19","guid":{"rendered":"http:\/\/haisins.epac.to\/wordpress\/?p=4670"},"modified":"2023-04-26T14:10:31","modified_gmt":"2023-04-26T05:10:31","slug":"rman-%eb%b0%b1%ec%97%85-%eb%b0%9b%eb%8a%94-%eb%8f%99%ec%95%88-%eb%b0%b1%ec%97%85-%ec%82%ac%ec%9d%b4%ec%a6%88-%ed%99%95%ec%9d%b8","status":"publish","type":"post","link":"http:\/\/haisins.synology.me\/wordpress\/?p=4670","title":{"rendered":"RMAN \ubc31\uc5c5 \ubc1b\ub294 \ub3d9\uc548 \ubc31\uc5c5 \uc0ac\uc774\uc988 \ud655\uc778"},"content":{"rendered":"
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RMAN \uc73c\ub85c \ubc31\uc5c5 \ubc1b\ub294 \ub3d9\uc548 \ubc31\uc5c5 \uc0ac\uc774\uc988 \ud655\uc778 \ucffc\ub9ac<\/div>\n<\/div>\n
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select type, status, filename, buffer_size, buffer_count <\/strong>from v$backup_async_io <\/strong>where type <> ‘AGGREGATE’<\/strong>and status = ‘IN PROGRESS’;<\/strong><\/div>\n<\/blockquote>\n<\/div>\n
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\uadf8\ub9ac\uace0 \ubc31\uc5c5 \uc0ac\uc774\uc988\ub97c \uc870\uc808\ud558\ub294 \ubc29\ubc95<\/div>\n<\/div>\n
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Let’s use the concepts and play with\u00a0MAXSETSIZE, MAXPIECESIZE, FILESPERSET, SECTION SIZE, MAXOPENFILES.<\/strong><\/p>\n

For the examples, I will use the following database:<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> report schema;<\/span><\/strong><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Report <\/span>of<\/span> database schema <\/span>for<\/span> database with db_unique_name DWQUAL01<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Permanent Datafiles<\/span><\/div>\n<\/div>\n
\n
===========================<\/span><\/div>\n<\/div>\n
\n
File <\/span>Size<\/span>(<\/span>MB<\/span>)<\/span> Tablespace RB segs Datafile Name<\/span><\/div>\n<\/div>\n
\n
—- ——– ——————– ——- ————————<\/span><\/div>\n<\/div>\n
\n
1<\/span> 840<\/span> SYSTEM <\/span>***<\/span> +DATA\/dwqual01\/datafile\/system.<\/span>266<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
2<\/span> 1020<\/span> SYSAUX <\/span>***<\/span> +DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
3<\/span> 610<\/span> UNDOTBS1 <\/span>***<\/span> +DATA\/dwqual01\/datafile\/undotbs1.<\/span>267<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
4<\/span> 5<\/span> USERS <\/span>***<\/span> +DATA\/dwqual01\/datafile\/users.<\/span>270<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
5<\/span> 256<\/span> AUDTBS <\/span>***<\/span> +DATA\/dwqual01\/datafile\/audtbs.<\/span>268<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
6<\/span> 15<\/span> DVTBS <\/span>***<\/span> +DATA\/dwqual01\/datafile\/dvtbs.<\/span>269<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

MAXSETSIZE<\/strong><\/h4>\n

Defines the maximum size of a backup set. The default MAXSETSIZE for a database is\u00a0unlimited<\/strong>.<\/p>\n

For the example above, if I put the MAXSETSIZE to\u00a01019M<\/strong>, the backup fails:<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> CONFIGURE MAXSETSIZE TO 1019M;<\/span><\/strong><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters:<\/span><\/div>\n<\/div>\n
\n
CONFIGURE MAXSETSIZE TO <\/span>1019<\/span> M;<\/span><\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters are successfully stored<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> backup database;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>00571<\/span>: ===========================================================<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>00569<\/span>: =============== ERROR MESSAGE STACK FOLLOWS ===============<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>00571<\/span>: ===========================================================<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>03002<\/span>: failure <\/span>of<\/span> backup command at <\/span>01<\/span>\/<\/span>31<\/span>\/<\/span>2015<\/span> 19<\/span>:<\/span>16<\/span>:<\/span>31<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>06183<\/span>: datafile or datafile copy +DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span> (<\/span>file number <\/span>2<\/span>)<\/span> larger than MAXSETSIZE<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

But if I change the MAXSETSIZE to 1020M, the backup will run:<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> CONFIGURE MAXSETSIZE TO 1020M;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
old RMAN configuration parameters:<\/span><\/div>\n<\/div>\n
\n
CONFIGURE MAXSETSIZE TO <\/span>1019<\/span> M;<\/span><\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters:<\/span><\/div>\n<\/div>\n
\n
CONFIGURE MAXSETSIZE TO <\/span>1020<\/span> M;<\/span><\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters are successfully stored<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> backup database;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
…<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

Why?\u00a0Because one datafile cannot\u00a0never<\/strong>\u00a0be placed in more than one backup set (I’ve already told that in the theory section).
\nIf I limit the size of a backup set to a value lower than my biggest datafile, it won’t fit there.
\nSo, remember, that\u00a0MAXSETSIZE<\/strong>\u00a0should be at least as large as the largest datafile.<\/p>\n

MAXPIECESIZE<\/strong><\/h4>\n

Defines the maximum size of a backup piece. The default MAXPIECESIZE is\u00a0unlimited<\/strong>.<\/p>\n

When it is set to default, your backup set is\u00a0usually stored in 1 backup piece (if to disk, this means one file per set).<\/p>\n

Let’s run a simple backup and check:<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> backup database;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
allocated channel: ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: SID=<\/span>227<\/span> device type=DISK<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting full datafile backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: specifying <\/span>datafile<\/span>(<\/span>s<\/span>)<\/span> in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00002<\/span> name=+DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00001<\/span> name=+DATA\/dwqual01\/datafile\/system.<\/span>266<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00003<\/span> name=+DATA\/dwqual01\/datafile\/undotbs1.<\/span>267<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00005<\/span> name=+DATA\/dwqual01\/datafile\/audtbs.<\/span>268<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00006<\/span> name=+DATA\/dwqual01\/datafile\/dvtbs.<\/span>269<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00004<\/span> name=+DATA\/dwqual01\/datafile\/users.<\/span>270<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
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channel ORA_DISK_1: starting piece <\/span>1<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>1<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t232750_0.<\/span>628<\/span>.<\/span>870478071<\/span> tag=TAG20150131T232750 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: backup set complete, elapsed time: <\/span>00<\/span>:<\/span>00<\/span>:<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting full datafile backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: specifying <\/span>datafile<\/span>(<\/span>s<\/span>)<\/span> in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
including current control file <\/span>in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
including current SPFILE <\/span>in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting piece <\/span>1<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>1<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_01_31\/ncsnf0_tag20150131t232750_0.<\/span>627<\/span>.<\/span>870478087<\/span> tag=TAG20150131T232750 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: backup set complete, elapsed time: <\/span>00<\/span>:<\/span>00<\/span>:<\/span>01<\/span><\/div>\n<\/div>\n
\n
Finished backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> list backup;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Backup Sets<\/span><\/div>\n<\/div>\n
\n
===================<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
BS Key Type LV Size Device Type Elapsed Time Completion Time<\/span><\/div>\n<\/div>\n
\n
——- —- — ———- ———– ———— —————<\/span><\/div>\n<\/div>\n
\n
60<\/span> Full <\/span>1.44<\/span>G DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>08<\/span> 31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
BP Key: <\/span>600<\/span> Status: AVAILABLE Compressed: NO Tag: TAG20150131T232750<\/span><\/div>\n<\/div>\n
\n
Piece Name: +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t232750_0.<\/span>628<\/span>.<\/span>870478071<\/span><\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Datafiles <\/span>in<\/span> backup set <\/span>60<\/span><\/div>\n<\/div>\n
\n
File LV Type Ckp SCN Ckp Time Name<\/span><\/div>\n<\/div>\n
\n
—- — —- ———- ——— —-<\/span><\/div>\n<\/div>\n
\n
1<\/span> Full <\/span>1011911<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/system.<\/span>266<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
2<\/span> Full <\/span>1011911<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
3<\/span> Full <\/span>1011911<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/undotbs1.<\/span>267<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
4<\/span> Full <\/span>1011911<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/users.<\/span>270<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
5<\/span> Full <\/span>1011911<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/audtbs.<\/span>268<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
6<\/span> Full <\/span>1011911<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/dvtbs.<\/span>269<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
BS Key Type LV Size Device Type Elapsed Time Completion Time<\/span><\/div>\n<\/div>\n
\n
——- —- — ———- ———– ———— —————<\/span><\/div>\n<\/div>\n
\n
61<\/span> Full <\/span>13.73<\/span>M DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>01<\/span> 31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
BP Key: <\/span>601<\/span> Status: AVAILABLE Compressed: NO Tag: TAG20150131T232750<\/span><\/div>\n<\/div>\n
\n
Piece Name: +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/ncsnf0_tag20150131t232750_0.<\/span>627<\/span>.<\/span>870478087<\/span><\/div>\n<\/div>\n
\n
SPFILE Included: Modification time: <\/span>30<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
SPFILE db_unique_name: DWQUAL01<\/span><\/div>\n<\/div>\n
\n
Control File Included: Ckp SCN: <\/span>1011921<\/span> Ckp time: <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

As you can check above, simply running “backup database” with all the default configuration will create one backup set with all the datafiles, stored in a single backup piece, and another backup set with the spfile and control file in another single backup piece.<\/p>\n

Now let’s change the MAXPIECESIZE to\u00a050M<\/strong>\u00a0and simulate the backup of one tablespace:<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> CONFIGURE CHANNEL DEVICE TYPE DISK MAXPIECESIZE 50M;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters:<\/span><\/div>\n<\/div>\n
\n
CONFIGURE CHANNEL DEVICE TYPE DISK MAXPIECESIZE <\/span>50<\/span> M;<\/span><\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters are successfully stored<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> backup tablespace sysaux;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
allocated channel: ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: SID=<\/span>152<\/span> device type=DISK<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting compressed full datafile backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: specifying <\/span>datafile<\/span>(<\/span>s<\/span>)<\/span> in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00002<\/span> name=+DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting piece <\/span>1<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>1<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t192933_0.<\/span>633<\/span>.<\/span>870463773<\/span> tag=TAG20150131T192933 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting piece <\/span>2<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>2<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t192933_0.<\/span>632<\/span>.<\/span>870463777<\/span> tag=TAG20150131T192933 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting piece <\/span>3<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>3<\/span> at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t192933_0.<\/span>631<\/span>.<\/span>870463777<\/span> tag=TAG20150131T192933 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: backup set complete, elapsed time: <\/span>00<\/span>:<\/span>00<\/span>:<\/span>05<\/span><\/div>\n<\/div>\n
\n
Finished backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> list backup;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Backup Sets<\/span><\/div>\n<\/div>\n
\n
===================<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
BS Key Type LV Size Device Type Elapsed Time Completion Time<\/span><\/div>\n<\/div>\n
\n
——- —- — ———- ———– ———— —————<\/span><\/div>\n<\/div>\n
\n
56<\/span> Full <\/span>91.97<\/span>M DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>04<\/span> 31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Datafiles <\/span>in<\/span> backup set <\/span>56<\/span><\/div>\n<\/div>\n
\n
File LV Type Ckp SCN Ckp Time Name<\/span><\/div>\n<\/div>\n
\n
—- — —- ———- ——— —-<\/span><\/div>\n<\/div>\n
\n
2<\/span> Full <\/span>1000573<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Backup Set Copy<\/span> #1 of backup set 56<\/span><\/div>\n<\/div>\n
\n
Device Type Elapsed Time Completion Time Compressed Tag<\/span><\/div>\n<\/div>\n
\n
———– ———— ————— ———- —<\/span><\/div>\n<\/div>\n
\n
DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>04<\/span> 31<\/span>-JAN-<\/span>15<\/span> YES TAG20150131T192933<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Backup Pieces <\/span>for<\/span> backup set <\/span>56<\/span> Copy<\/span> #1<\/span><\/div>\n<\/div>\n
\n
BP Key P<\/span>c# Status Piece Name<\/span><\/div>\n<\/div>\n
\n
——- — ———– ———-<\/span><\/div>\n<\/div>\n
\n
562<\/span> 1<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t192933_0.<\/span>633<\/span>.<\/span>870463773<\/span><\/div>\n<\/div>\n
\n
563<\/span> 2<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t192933_0.<\/span>632<\/span>.<\/span>870463777<\/span><\/div>\n<\/div>\n
\n
564<\/span> 3<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t192933_0.<\/span>631<\/span>.<\/span>870463777<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

So here we have one backup set composed of 3 backup pieces (files). Why would you ever do this?
\nThis is useful if you cannot create backup files bigger than X bytes due to restrictions of your OS or you want to move it to several media disks that have a size limit. It can also be a limit\u00a0imposed by your media manager software.<\/p>\n

FILESPERSET<\/h4>\n

Specify the maximum number of files in each backup set.\u00a0The FILESPERSET default is\u00a064<\/strong>.<\/p>\n

The real number of files in each backup set is\u00a0the minimum of the FILESPERSET setting and the number of files read by each channel.<\/p>\n

So if you are backing up only 2\u00a0datafiles, and filesperset is 3, you will have only 2 datafiles in your backup set. Otherwise you are a wizard.<\/p>\n

Let’s change the filesperset to 2 and test:<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> backup database filesperset <\/span>2<\/span>;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
…<\/span><\/div>\n<\/div>\n
\n
Finished backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> list backup;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Backup Sets<\/span><\/div>\n<\/div>\n
\n
===================<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
BS Key Type LV Size Device Type Elapsed Time Completion Time<\/span><\/div>\n<\/div>\n
\n
——- —- — ———- ———– ———— —————<\/span><\/div>\n<\/div>\n
\n
63<\/span> Full <\/span>87.97<\/span>M DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>03<\/span> 31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
BP Key: <\/span>605<\/span> Status: AVAILABLE Compressed: YES Tag: TAG20150131T234910<\/span><\/div>\n<\/div>\n
\n
Piece Name: +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t234910_0.<\/span>626<\/span>.<\/span>870479351<\/span><\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Datafiles <\/span>in<\/span> backup set <\/span>63<\/span><\/div>\n<\/div>\n
\n
File LV Type Ckp SCN Ckp Time Name<\/span><\/div>\n<\/div>\n
\n
—- — —- ———- ——— —-<\/span><\/div>\n<\/div>\n
\n
2<\/span> Full <\/span>1012713<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
4<\/span> Full <\/span>1012713<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/users.<\/span>270<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
BS Key Type LV Size Device Type Elapsed Time Completion Time<\/span><\/div>\n<\/div>\n
\n
——- —- — ———- ———– ———— —————<\/span><\/div>\n<\/div>\n
\n
64<\/span> Full <\/span>5.34<\/span>M DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>01<\/span> 31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
BP Key: <\/span>606<\/span> Status: AVAILABLE Compressed: YES Tag: TAG20150131T234910<\/span><\/div>\n<\/div>\n
\n
Piece Name: +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t234910_0.<\/span>628<\/span>.<\/span>870479357<\/span><\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Datafiles <\/span>in<\/span> backup set <\/span>64<\/span><\/div>\n<\/div>\n
\n
File LV Type Ckp SCN Ckp Time Name<\/span><\/div>\n<\/div>\n
\n
—- — —- ———- ——— —-<\/span><\/div>\n<\/div>\n
\n
3<\/span> Full <\/span>1012716<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/undotbs1.<\/span>267<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
5<\/span> Full <\/span>1012716<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/audtbs.<\/span>268<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
BS Key Type LV Size Device Type Elapsed Time Completion Time<\/span><\/div>\n<\/div>\n
\n
——- —- — ———- ———– ———— —————<\/span><\/div>\n<\/div>\n
\n
65<\/span> Full <\/span>157.69<\/span>M DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>04<\/span> 31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
BP Key: <\/span>607<\/span> Status: AVAILABLE Compressed: YES Tag: TAG20150131T234910<\/span><\/div>\n<\/div>\n
\n
Piece Name: +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/nnndf0_tag20150131t234910_0.<\/span>627<\/span>.<\/span>870479361<\/span><\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Datafiles <\/span>in<\/span> backup set <\/span>65<\/span><\/div>\n<\/div>\n
\n
File LV Type Ckp SCN Ckp Time Name<\/span><\/div>\n<\/div>\n
\n
—- — —- ———- ——— —-<\/span><\/div>\n<\/div>\n
\n
1<\/span> Full <\/span>1012718<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/system.<\/span>266<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
6<\/span> Full <\/span>1012718<\/span> 31<\/span>-JAN-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/dvtbs.<\/span>269<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
BS Key Type LV Size Device Type Elapsed Time Completion Time<\/span><\/div>\n<\/div>\n
\n
——- —- — ———- ———– ———— —————<\/span><\/div>\n<\/div>\n
\n
66<\/span> Full <\/span>4.09<\/span>M DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>01<\/span> 31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
BP Key: <\/span>608<\/span> Status: AVAILABLE Compressed: YES Tag: TAG20150131T234910<\/span><\/div>\n<\/div>\n
\n
Piece Name: +ARCHIVE\/dwqual01\/backupset\/2015_01_31\/ncsnf0_tag20150131t234910_0.<\/span>625<\/span>.<\/span>870479369<\/span><\/div>\n<\/div>\n
\n
SPFILE Included: Modification time: <\/span>30<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
SPFILE db_unique_name: DWQUAL01<\/span><\/div>\n<\/div>\n
\n
Control File Included: Ckp SCN: <\/span>1012721<\/span> Ckp time: <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

As you can see above, each backup set has now only 2 datafiles.<\/p>\n

SECTION SIZE<\/h4>\n

It is useful when you want to enable RMAN channels to back up a single large file in parallel. RMAN divides the work among multiple channels, with each channel backing up one file section in a backup piece. Backing up a file in separate sections can improve the performance of backups of large datafiles.<\/p>\n

If you specify a section size that is larger than the size of the file, then RMAN does not use multisection backup for the file. If you specify a small section size that would produce more than 256 sections, then RMAN increases the section size to a value that results in exactly 256 sections.<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> backup tablespace sysaux section size 1M;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_2<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_3<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_4<\/span><\/div>\n<\/div>\n
\n
…<\/span><\/div>\n<\/div>\n
\n
Finished backup at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> list backup;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Backup Sets<\/span><\/div>\n<\/div>\n
\n
===================<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
BS Key Type LV Size Device Type Elapsed Time Completion Time<\/span><\/div>\n<\/div>\n
\n
——- —- — ———- ———– ———— —————<\/span><\/div>\n<\/div>\n
\n
100<\/span> Full <\/span>767.13<\/span>M DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>38<\/span> 01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Datafiles <\/span>in<\/span> backup set <\/span>100<\/span><\/div>\n<\/div>\n
\n
File LV Type Ckp SCN Ckp Time Name<\/span><\/div>\n<\/div>\n
\n
—- — —- ———- ——— —-<\/span><\/div>\n<\/div>\n
\n
2<\/span> Full <\/span>1042081<\/span> 01<\/span>-FEB-<\/span>15<\/span> +DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Backup Set Copy<\/span> #1 of backup set 100<\/span><\/div>\n<\/div>\n
\n
Device Type Elapsed Time Completion Time Compressed Tag<\/span><\/div>\n<\/div>\n
\n
———– ———— ————— ———- —<\/span><\/div>\n<\/div>\n
\n
DISK <\/span>00<\/span>:<\/span>00<\/span>:<\/span>38<\/span> 01<\/span>-FEB-<\/span>15<\/span> YES TAG20150201T102000<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
List <\/span>of<\/span> Backup Pieces <\/span>for<\/span> backup set <\/span>100<\/span> Copy<\/span> #1<\/span><\/div>\n<\/div>\n
\n
BP Key P<\/span>c# Status Piece Name<\/span><\/div>\n<\/div>\n
\n
——- — ———– ———-<\/span><\/div>\n<\/div>\n
\n
701<\/span> 1<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t102000_0.<\/span>618<\/span>.<\/span>870517201<\/span><\/div>\n<\/div>\n
\n
702<\/span> 2<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t102000_0.<\/span>611<\/span>.<\/span>870517201<\/span><\/div>\n<\/div>\n
\n
703<\/span> 3<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t102000_0.<\/span>619<\/span>.<\/span>870517201<\/span><\/div>\n<\/div>\n
\n
…<\/div>\n<\/div>\n
\n
952<\/span> 252<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t102000_0.<\/span>318<\/span>.<\/span>870517237<\/span><\/div>\n<\/div>\n
\n
953<\/span> 253<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t102000_0.<\/span>319<\/span>.<\/span>870517237<\/span><\/div>\n<\/div>\n
\n
954<\/span> 254<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t102000_0.<\/span>320<\/span>.<\/span>870517237<\/span><\/div>\n<\/div>\n
\n
955<\/span> 255<\/span> AVAILABLE +ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t102000_0.<\/span>321<\/span>.<\/span>870517239<\/span><\/div>\n<\/div>\n
\n
256<\/span> DELETED<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

You cannot specify\u00a0SECTION SIZE<\/strong>\u00a0in conjunction with\u00a0MAXPIECESIZE<\/strong>. Why?<\/p>\n

Because if you have a datafile like my SYSAUX of 1020M and defines SECTION SIZE of 100M with parallelism of 4, this means that each backup thread will read 100M \/ 1020M. So it\u00a0will be read 11 times in parallel by those 4 threads. Each thread will generate\u00a0one backup piece<\/strong>.<\/p>\n

The idea of MAXPIECESIZE is to limit a backup piece to a size. This error would appear if I mix the 2 commands (note that MAXPIECESIZE\u00a0is still in the default configuration):<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> backup tablespace sysaux section size 50M;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>31<\/span>-JAN-<\/span>15<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_2<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_3<\/span><\/div>\n<\/div>\n
\n
using channel ORA_DISK_4<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>00571<\/span>: ===========================================================<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>00569<\/span>: =============== ERROR MESSAGE STACK FOLLOWS ===============<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>00571<\/span>: ===========================================================<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>03002<\/span>: failure <\/span>of<\/span> backup command at <\/span>01<\/span>\/<\/span>31<\/span>\/<\/span>2015<\/span> 19<\/span>:<\/span>40<\/span>:<\/span>01<\/span><\/div>\n<\/div>\n
\n
RMAN-<\/span>06808<\/span>: SECTION SIZE cannot be used when piece limit is <\/span>in<\/span> effect<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

When you use SECTION SIZE and run any kind of backup, each generated\u00a0backup set will have\u00a0only\u00a0one<\/strong>\u00a0database file.<\/p>\n

MAXOPENFILES<\/strong><\/h4>\n

This defines the number of files that can be read simultaneously by each channel. The MAXOPENFILES default is 8.<\/p>\n

If you set it to 1 or 8 and backup your database with a single channel, you will still have, as the first example,\u00a0one backup set with all the datafiles, stored in a single backup piece, and another backup set with the spfile and control file in another single backup piece.<\/p>\n

What will change is the distribution inside the backup set. With 1, as it will read one datafile at a time, it will write the backup data into the backup piece sequentially. With 8, the backup piece will have data from all the 8 datafiles mixed.<\/p>\n

Let’s test it. I will run with MAXOPENFILES to 1 and RATE to 50 MB so the backup does not finish so fast.<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> CONFIGURE CHANNEL DEVICE TYPE DISK MAXOPENFILES <\/span>1<\/span> rate 50M;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters:<\/span><\/div>\n<\/div>\n
\n
CONFIGURE CHANNEL DEVICE TYPE DISK MAXOPENFILES <\/span>1<\/span> RATE <\/span>50<\/span> M;<\/span><\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters are successfully stored<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> backup database;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
allocated channel: ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: SID=<\/span>503<\/span> device type=DISK<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting full datafile backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: specifying <\/span>datafile<\/span>(<\/span>s<\/span>)<\/span> in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00002<\/span> name=+DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00001<\/span> name=+DATA\/dwqual01\/datafile\/system.<\/span>266<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00003<\/span> name=+DATA\/dwqual01\/datafile\/undotbs1.<\/span>267<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00005<\/span> name=+DATA\/dwqual01\/datafile\/audtbs.<\/span>268<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00006<\/span> name=+DATA\/dwqual01\/datafile\/dvtbs.<\/span>269<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00004<\/span> name=+DATA\/dwqual01\/datafile\/users.<\/span>270<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting piece <\/span>1<\/span> at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>1<\/span> at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t113026_0.<\/span>621<\/span>.<\/span>870521427<\/span> tag=TAG20150201T113026 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: backup set complete, elapsed time: <\/span>00<\/span>:<\/span>01<\/span>:<\/span>05<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: throttle time: <\/span>0<\/span>:<\/span>00<\/span>:<\/span>49<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting full datafile backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: specifying <\/span>datafile<\/span>(<\/span>s<\/span>)<\/span> in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
including current control file <\/span>in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
including current SPFILE <\/span>in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting piece <\/span>1<\/span> at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>1<\/span> at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_02_01\/ncsnf0_tag20150201t113026_0.<\/span>624<\/span>.<\/span>870521493<\/span> tag=TAG20150201T113026 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: backup set complete, elapsed time: <\/span>00<\/span>:<\/span>00<\/span>:<\/span>01<\/span><\/div>\n<\/div>\n
\n
Finished backup at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

While it is running, in another sqlplus screen I run:<\/p>\n

\n
\n
\n
SQL<\/span>><\/span> col filename <\/span>for<\/span> a25 word_wrapped<\/span><\/div>\n<\/div>\n
\n
SQL<\/span>><\/span> select type, status, filename, buffer_size, buffer_count<\/span><\/div>\n<\/div>\n
\n
2<\/span> from v$backup_async_io<\/span><\/div>\n<\/div>\n
\n
3<\/span> where type <\/span><><\/span> ‘AGGREGATE’<\/span><\/div>\n<\/div>\n
\n
4<\/span> and status = <\/span>‘IN PROGRESS’<\/span>;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
TYPE STATUS FILENAME BUFFER_SIZE BUFFER_COUNT<\/span><\/div>\n<\/div>\n
\n
——— ———– ————————- ———– ————<\/span><\/div>\n<\/div>\n
\n
INPUT <\/span>IN<\/span> PROGRESS +DATA\/dwqual01\/datafile\/s <\/span>1048576<\/span> 16<\/span><\/div>\n<\/div>\n
\n
ysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
OUTPUT <\/span>IN<\/span> PROGRESS +ARCHIVE\/dwqual01\/backups <\/span>4194304<\/span> 4<\/span><\/div>\n<\/div>\n
\n
et\/2015_02_01\/nnndf0_tag2<\/span><\/div>\n<\/div>\n
\n
0150201t113026_0.<\/span>621<\/span>.<\/span>8705<\/span><\/div>\n<\/div>\n
\n
21427<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
SQL<\/span>><\/span> \/<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
TYPE STATUS FILENAME BUFFER_SIZE BUFFER_COUNT<\/span><\/div>\n<\/div>\n
\n
——— ———– ————————- ———– ————<\/span><\/div>\n<\/div>\n
\n
INPUT <\/span>IN<\/span> PROGRESS +DATA\/dwqual01\/datafile\/s <\/span>1048576<\/span> 16<\/span><\/div>\n<\/div>\n
\n
ystem.<\/span>266<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
OUTPUT <\/span>IN<\/span> PROGRESS +ARCHIVE\/dwqual01\/backups <\/span>4194304<\/span> 4<\/span><\/div>\n<\/div>\n
\n
et\/2015_02_01\/nnndf0_tag2<\/span><\/div>\n<\/div>\n
\n
0150201t113026_0.<\/span>621<\/span>.<\/span>8705<\/span><\/div>\n<\/div>\n
\n
21427<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
SQL<\/span>><\/span> \/<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
TYPE STATUS FILENAME BUFFER_SIZE BUFFER_COUNT<\/span><\/div>\n<\/div>\n
\n
——— ———– ————————- ———– ————<\/span><\/div>\n<\/div>\n
\n
INPUT <\/span>IN<\/span> PROGRESS +DATA\/dwqual01\/datafile\/u <\/span>1048576<\/span> 16<\/span><\/div>\n<\/div>\n
\n
ndotbs1.<\/span>267<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
OUTPUT <\/span>IN<\/span> PROGRESS +ARCHIVE\/dwqual01\/backups <\/span>4194304<\/span> 4<\/span><\/div>\n<\/div>\n
\n
et\/2015_02_01\/nnndf0_tag2<\/span><\/div>\n<\/div>\n
\n
0150201t113026_0.<\/span>621<\/span>.<\/span>8705<\/span><\/div>\n<\/div>\n
\n
21427<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

As we can see it reads each datafile at a time.<\/p>\n

Now with MAXOPENFILES\u00a0set to 2:<\/p>\n

\n
\n
\n
RMAN<\/span>><\/span> CONFIGURE CHANNEL DEVICE TYPE DISK MAXOPENFILES <\/span>2<\/span> rate 50M;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters:<\/span><\/div>\n<\/div>\n
\n
CONFIGURE CHANNEL DEVICE TYPE DISK MAXOPENFILES <\/span>2<\/span> RATE <\/span>50<\/span> M;<\/span><\/div>\n<\/div>\n
\n
new<\/span> RMAN configuration parameters are successfully stored<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span> backup database;<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
Starting backup at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
allocated channel: ORA_DISK_1<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: SID=<\/span>503<\/span> device type=DISK<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting full datafile backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: specifying <\/span>datafile<\/span>(<\/span>s<\/span>)<\/span> in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00002<\/span> name=+DATA\/dwqual01\/datafile\/sysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00001<\/span> name=+DATA\/dwqual01\/datafile\/system.<\/span>266<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00003<\/span> name=+DATA\/dwqual01\/datafile\/undotbs1.<\/span>267<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00005<\/span> name=+DATA\/dwqual01\/datafile\/audtbs.<\/span>268<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00006<\/span> name=+DATA\/dwqual01\/datafile\/dvtbs.<\/span>269<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
input datafile file number=<\/span>00004<\/span> name=+DATA\/dwqual01\/datafile\/users.<\/span>270<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting piece <\/span>1<\/span> at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>1<\/span> at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_02_01\/nnndf0_tag20150201t120227_0.<\/span>611<\/span>.<\/span>870523349<\/span> tag=TAG20150201T120227 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: backup set complete, elapsed time: <\/span>00<\/span>:<\/span>00<\/span>:<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting full datafile backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: specifying <\/span>datafile<\/span>(<\/span>s<\/span>)<\/span> in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
including current control file <\/span>in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
including current SPFILE <\/span>in<\/span> backup set<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: starting piece <\/span>1<\/span> at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: finished piece <\/span>1<\/span> at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
piece handle=+ARCHIVE\/dwqual01\/backupset\/2015_02_01\/ncsnf0_tag20150201t120227_0.<\/span>618<\/span>.<\/span>870523365<\/span> tag=TAG20150201T120227 comment=NONE<\/span><\/div>\n<\/div>\n
\n
channel ORA_DISK_1: backup set complete, elapsed time: <\/span>00<\/span>:<\/span>00<\/span>:<\/span>01<\/span><\/div>\n<\/div>\n
\n
Finished backup at <\/span>01<\/span>-FEB-<\/span>15<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
RMAN<\/span>><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

Checking with\u00a0sqlplus:<\/p>\n

\n
\n
\n
SQL<\/span>><\/span> \/<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
TYPE STATUS FILENAME BUFFER_SIZE BUFFER_COUNT<\/span><\/div>\n<\/div>\n
\n
——— ———– ————————- ———– ————<\/span><\/div>\n<\/div>\n
\n
INPUT <\/span>IN<\/span> PROGRESS +DATA\/dwqual01\/datafile\/s <\/span>1048576<\/span> 8<\/span><\/div>\n<\/div>\n
\n
ysaux.<\/span>265<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
INPUT <\/span>IN<\/span> PROGRESS +DATA\/dwqual01\/datafile\/s <\/span>1048576<\/span> 8<\/span><\/div>\n<\/div>\n
\n
ystem.<\/span>266<\/span>.<\/span>870358459<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
OUTPUT <\/span>IN<\/span> PROGRESS +ARCHIVE\/dwqual01\/backups <\/span>4194304<\/span> 4<\/span><\/div>\n<\/div>\n
\n
et\/2015_02_01\/nnndf0_tag2<\/span><\/div>\n<\/div>\n
\n
0150201t120227_0.<\/span>611<\/span>.<\/span>8705<\/span><\/div>\n<\/div>\n
\n
23349<\/span><\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
<\/div>\n<\/div>\n
\n
SQL<\/span>><\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

As we can see, now my rman channel is reading from 2 datafiles simultaneously. Thus, my level of multiplexing here is 2.<\/p>\n

Remeber, in case files being backed up are ASM files, level of multiplexing may be reduced as ASM\u00a0automatically takes care of the contention by striping the data. So a MAXOPENFILES of 5 does not necessarily means that you will have a\u00a0multiplexing level of 5 when you backup to ASM.<\/p>\n

\n

External pages that helped in this article:<\/p>\n

    \n
  • http:\/\/oracleinaction.com\/tune-rman-i\/<\/li>\n
  • http:\/\/docs.oracle.com\/cd\/E11882_01\/backup.112\/e10642\/glossary.htm#CHDHHBFC<\/li>\n<\/ul>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

    RMAN \uc73c\ub85c \ubc31\uc5c5 \ubc1b\ub294 \ub3d9\uc548 \ubc31\uc5c5 \uc0ac\uc774\uc988 \ud655\uc778 \ucffc\ub9ac select type, status, filename, buffer_size, buffer_count from v$backup_async_io where type <> ‘AGGREGATE’and status = ‘IN PROGRESS’; \uadf8\ub9ac\uace0 \ubc31\uc5c5 \uc0ac\uc774\uc988\ub97c \uc870\uc808\ud558\ub294 \ubc29\ubc95 Let’s use the concepts and play with\u00a0MAXSETSIZE, MAXPIECESIZE, FILESPERSET, SECTION SIZE, MAXOPENFILES. For the examples, I will use the following database: RMAN> report schema; Report […]<\/p>\n","protected":false},"author":1,"featured_media":3435,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"spay_email":""},"categories":[3],"tags":[291,77],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/haisins.synology.me\/wordpress\/wp-content\/uploads\/2018\/02\/databackup_article_008.jpg?fit=1200%2C400","amp_enabled":true,"_links":{"self":[{"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4670"}],"collection":[{"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4670"}],"version-history":[{"count":2,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4670\/revisions"}],"predecessor-version":[{"id":4893,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/4670\/revisions\/4893"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=\/wp\/v2\/media\/3435"}],"wp:attachment":[{"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4670"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4670"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/haisins.synology.me\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4670"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}