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Question and Answer

Connor McDonald

Thanks for the question, Brice.

Asked: September 24, 2019 - 5:40 pm UTC

Last updated: September 25, 2019 - 5:42 am UTC

Version: 12.2.0.1

Viewed 10K+ times! This question is

You Asked

HELLO ,
i've made some test to try to parallelizethe best the backup of bigdatabase and i wanted to know if it's possible to parallelize the backup of a backuppiece (multiple backupset) on mulitple channel with maxpiecesize because our SBT media is limited to 190 Go (and there is deadlock in restauration if backuppiece is in multiple media):


CONFIGURE DEVICE TYPE 'SBT_TAPE' PARALLELISM 4 BACKUP TYPE TO BACKUPSET;


SECTION SIZE :
- it's ok on multiple channel but this attribute the number of channel with the calcul for example in bigfile :
Size of tablespace/ SECTION SIZE = number of channels
but if the tbablespace is 50% used it will attribute channel for the 100% and 50% of channels will backup nothing.



MAXPIECESIZE :
-it's better because it don't give channel to save "nothing" but if i had 4 channel the bigger tablespace will be backup only on the same channel and when other files finish to be backuped the only one channel is used to finish the bigest so
- it open the channel c1 save MAXPIECESIZE of the file
- close the channel c1
- open the channel c1 save MAXPIECESIZE of the file
- close the channel c1
- open the channel c1 save MAXPIECESIZE of the file
- close the channel c1

so the channels c2,c3,c4 are not used ....

is there a way to parallize this ?


thank's for your help

and Connor said...

Isn't this just a case of picking an appropriate multiplier for your section size ?

For example, I did:

RMAN> configure device type disk parallelism 4;

using target database control file instead of recovery catalog
old RMAN configuration parameters:
CONFIGURE DEVICE TYPE DISK PARALLELISM 4 BACKUP TYPE TO BACKUPSET;
new RMAN configuration parameters:
CONFIGURE DEVICE TYPE DISK PARALLELISM 4 BACKUP TYPE TO BACKUPSET;
new RMAN configuration parameters are successfully stored


So I'll have a parallelism of 4.

I have a tablespace LARGETS which is 16G in allocated file size with approx 1.5G of segments.

So as long as I pick a section size smaller than 1.5, the load should be spread across the 4 channels.

RMAN> backup tablespace largets section size 300m;

Starting backup at 25-SEP-19
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=865 device type=DISK
allocated channel: ORA_DISK_2
channel ORA_DISK_2: SID=983 device type=DISK
allocated channel: ORA_DISK_3
channel ORA_DISK_3: SID=1108 device type=DISK
allocated channel: ORA_DISK_4
channel ORA_DISK_4: SID=1228 device type=DISK
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1 through 38400
channel ORA_DISK_1: starting piece 1 at 25-SEP-19
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 38401 through 76800
channel ORA_DISK_2: starting piece 2 at 25-SEP-19
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 76801 through 115200
channel ORA_DISK_3: starting piece 3 at 25-SEP-19
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 115201 through 153600
channel ORA_DISK_4: starting piece 4 at 25-SEP-19
channel ORA_DISK_1: finished piece 1 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_1_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:02
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 153601 through 192000
channel ORA_DISK_1: starting piece 5 at 25-SEP-19
channel ORA_DISK_2: finished piece 2 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_2_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:05
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 192001 through 230400
channel ORA_DISK_2: starting piece 6 at 25-SEP-19
channel ORA_DISK_3: finished piece 3 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_3_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:05
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 230401 through 268800
channel ORA_DISK_3: starting piece 7 at 25-SEP-19
channel ORA_DISK_1: finished piece 5 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_5_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:05
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 268801 through 307200
channel ORA_DISK_1: starting piece 8 at 25-SEP-19
channel ORA_DISK_2: finished piece 6 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_6_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 307201 through 345600
channel ORA_DISK_2: starting piece 9 at 25-SEP-19
channel ORA_DISK_4: finished piece 4 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_4_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:06
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 345601 through 384000
channel ORA_DISK_4: starting piece 10 at 25-SEP-19
channel ORA_DISK_1: finished piece 8 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_8_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 384001 through 422400
channel ORA_DISK_1: starting piece 11 at 25-SEP-19
channel ORA_DISK_3: finished piece 7 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_7_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 422401 through 460800
channel ORA_DISK_3: starting piece 12 at 25-SEP-19
channel ORA_DISK_2: finished piece 9 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_9_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 460801 through 499200
channel ORA_DISK_2: starting piece 13 at 25-SEP-19
channel ORA_DISK_4: finished piece 10 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_10_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 499201 through 537600
channel ORA_DISK_4: starting piece 14 at 25-SEP-19
channel ORA_DISK_1: finished piece 11 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_11_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 537601 through 576000
channel ORA_DISK_1: starting piece 15 at 25-SEP-19
channel ORA_DISK_3: finished piece 12 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_12_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 576001 through 614400
channel ORA_DISK_3: starting piece 16 at 25-SEP-19
channel ORA_DISK_2: finished piece 13 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_13_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 614401 through 652800
channel ORA_DISK_2: starting piece 17 at 25-SEP-19
channel ORA_DISK_4: finished piece 14 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_14_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 652801 through 691200
channel ORA_DISK_4: starting piece 18 at 25-SEP-19
channel ORA_DISK_1: finished piece 15 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_15_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 691201 through 729600
channel ORA_DISK_1: starting piece 19 at 25-SEP-19
channel ORA_DISK_3: finished piece 16 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_16_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 729601 through 768000
channel ORA_DISK_3: starting piece 20 at 25-SEP-19
channel ORA_DISK_1: finished piece 19 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_19_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 768001 through 806400
channel ORA_DISK_1: starting piece 21 at 25-SEP-19
channel ORA_DISK_2: finished piece 17 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_17_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 806401 through 844800
channel ORA_DISK_2: starting piece 22 at 25-SEP-19
channel ORA_DISK_4: finished piece 18 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_18_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 844801 through 883200
channel ORA_DISK_4: starting piece 23 at 25-SEP-19
channel ORA_DISK_1: finished piece 21 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_21_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 883201 through 921600
channel ORA_DISK_1: starting piece 24 at 25-SEP-19
channel ORA_DISK_3: finished piece 20 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_20_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 921601 through 960000
channel ORA_DISK_3: starting piece 25 at 25-SEP-19
channel ORA_DISK_2: finished piece 22 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_22_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 960001 through 998400
channel ORA_DISK_2: starting piece 26 at 25-SEP-19
channel ORA_DISK_4: finished piece 23 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_23_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 998401 through 1036800
channel ORA_DISK_4: starting piece 27 at 25-SEP-19
channel ORA_DISK_1: finished piece 24 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_24_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1036801 through 1075200
channel ORA_DISK_1: starting piece 28 at 25-SEP-19
channel ORA_DISK_2: finished piece 26 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_26_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1075201 through 1113600
channel ORA_DISK_2: starting piece 29 at 25-SEP-19
channel ORA_DISK_3: finished piece 25 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_25_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1113601 through 1152000
channel ORA_DISK_3: starting piece 30 at 25-SEP-19
channel ORA_DISK_1: finished piece 28 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_28_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1152001 through 1190400
channel ORA_DISK_1: starting piece 31 at 25-SEP-19
channel ORA_DISK_4: finished piece 27 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_27_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1190401 through 1228800
channel ORA_DISK_4: starting piece 32 at 25-SEP-19
channel ORA_DISK_2: finished piece 29 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_29_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1228801 through 1267200
channel ORA_DISK_2: starting piece 33 at 25-SEP-19
channel ORA_DISK_3: finished piece 30 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_30_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1267201 through 1305600
channel ORA_DISK_3: starting piece 34 at 25-SEP-19
channel ORA_DISK_1: finished piece 31 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_31_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1305601 through 1344000
channel ORA_DISK_1: starting piece 35 at 25-SEP-19
channel ORA_DISK_4: finished piece 32 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_32_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1344001 through 1382400
channel ORA_DISK_4: starting piece 36 at 25-SEP-19
channel ORA_DISK_2: finished piece 33 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_33_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1382401 through 1420800
channel ORA_DISK_2: starting piece 37 at 25-SEP-19
channel ORA_DISK_3: finished piece 34 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_34_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1420801 through 1459200
channel ORA_DISK_3: starting piece 38 at 25-SEP-19
channel ORA_DISK_1: finished piece 35 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_35_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1459201 through 1497600
channel ORA_DISK_1: starting piece 39 at 25-SEP-19
channel ORA_DISK_4: finished piece 36 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_36_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1497601 through 1536000
channel ORA_DISK_4: starting piece 40 at 25-SEP-19
channel ORA_DISK_2: finished piece 37 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_37_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1536001 through 1574400
channel ORA_DISK_2: starting piece 41 at 25-SEP-19
channel ORA_DISK_3: finished piece 38 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_38_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1574401 through 1612800
channel ORA_DISK_3: starting piece 42 at 25-SEP-19
channel ORA_DISK_1: finished piece 39 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_39_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1612801 through 1651200
channel ORA_DISK_1: starting piece 43 at 25-SEP-19
channel ORA_DISK_2: finished piece 41 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_41_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1651201 through 1689600
channel ORA_DISK_2: starting piece 44 at 25-SEP-19
channel ORA_DISK_4: finished piece 40 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_40_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1689601 through 1728000
channel ORA_DISK_4: starting piece 45 at 25-SEP-19
channel ORA_DISK_1: finished piece 43 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_43_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1728001 through 1766400
channel ORA_DISK_1: starting piece 46 at 25-SEP-19
channel ORA_DISK_3: finished piece 42 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_42_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1766401 through 1804800
channel ORA_DISK_3: starting piece 47 at 25-SEP-19
channel ORA_DISK_2: finished piece 44 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_44_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1804801 through 1843200
channel ORA_DISK_2: starting piece 48 at 25-SEP-19
channel ORA_DISK_4: finished piece 45 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_45_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1843201 through 1881600
channel ORA_DISK_4: starting piece 49 at 25-SEP-19
channel ORA_DISK_1: finished piece 46 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_46_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1881601 through 1920000
channel ORA_DISK_1: starting piece 50 at 25-SEP-19
channel ORA_DISK_2: finished piece 48 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_48_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1920001 through 1958400
channel ORA_DISK_2: starting piece 51 at 25-SEP-19
channel ORA_DISK_3: finished piece 47 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_47_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_3: starting full datafile backup set
channel ORA_DISK_3: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1958401 through 1996800
channel ORA_DISK_3: starting piece 52 at 25-SEP-19
channel ORA_DISK_1: finished piece 50 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_50_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 1996801 through 2035200
channel ORA_DISK_1: starting piece 53 at 25-SEP-19
channel ORA_DISK_4: finished piece 49 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_49_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_4: starting full datafile backup set
channel ORA_DISK_4: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 2035201 through 2073600
channel ORA_DISK_4: starting piece 54 at 25-SEP-19
channel ORA_DISK_2: finished piece 51 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_51_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_2: starting full datafile backup set
channel ORA_DISK_2: specifying datafile(s) in backup set
input datafile file number=00013 name=X:\ORADATA\DB18\PDB1\LARGETS.DBF
backing up blocks 2073601 through 2076160
channel ORA_DISK_2: starting piece 55 at 25-SEP-19
channel ORA_DISK_3: finished piece 52 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_52_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_3: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_1: finished piece 53 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_53_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_4: finished piece 54 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_54_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_4: backup set complete, elapsed time: 00:00:00
channel ORA_DISK_2: finished piece 55 at 25-SEP-19
piece handle=X:\ORACLE\BKP\1KUCL963_55_1 tag=TAG20190925T131651 comment=NONE
channel ORA_DISK_2: backup set complete, elapsed time: 00:00:01
Finished backup at 25-SEP-19

RMAN>


Yes I'll end up with some "empty" (typically 64k) chunks but I'm still getting parallelism 4 with files capped at the section size



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