However, based on my below investigation, this feature is not efficient.
While waiting and waiting, which didn't complete within my expect time.
Then I am interested to know what happened, as the time is 5x than what was taken for a fresh LEVEL 0 backup.
Furthermore investigation shows the backupset size is 5.7x times larger than a fresh LEVEL 0 backupset.
This is very surprising. For this case, I learned it is better to have LEVEL 0 pre-created before running LEVEL 1.
Below are technical numbers.
--full backup size
testdbdev:TESTDB:/dbfra/testdbdev/TESTDB/backupset/2016_04_13> ls -lrt *T142516*
-rw-r----- 1 oratest oratest 8839168 Apr 13 13:43 o1_mf_nnndf_TAG20160413T142516_cjvsldnj_.bkp
-rw-r----- 1 oratest oratest 38264832 Apr 13 13:43 o1_mf_nnndf_TAG20160413T142516_cjvsw8k3_.bkp
-rw-r----- 1 oratest oratest 8224768 Apr 13 13:45 o1_mf_nnndf_TAG20160413T142516_cjvsx1vn_.bkp
-rw-r----- 1 oratest oratest 37568512 Apr 13 13:49 o1_mf_nnndf_TAG20160413T142516_cjvszfhs_.bkp
-rw-r----- 1 oratest oratest 2370019328 Apr 13 13:55 o1_mf_nnndf_TAG20160413T142516_cjvsldo0_.bkp
-rw-r----- 1 oratest oratest 2252800 Apr 13 13:56 o1_mf_nnndf_TAG20160413T142516_cjvtmrx9_.bkp
-rw-r----- 1 oratest oratest 17235968 Apr 13 13:56 o1_mf_nnndf_TAG20160413T142516_cjvtnw8y_.bkp
-rw-r----- 1 oratest oratest 18685952 Apr 13 13:57 o1_mf_nnndf_TAG20160413T142516_cjvtocmk_.bkp
-rw-r----- 1 oratest oratest 1310720 Apr 13 13:57 o1_mf_nnndf_TAG20160413T142516_cjvtphbl_.bkp
-rw-r----- 1 oratest oratest 2809856 Apr 13 13:58 o1_mf_nnndf_TAG20160413T142516_cjvtpyr6_.bkp
-rw-r----- 1 oratest oratest 2097152 Apr 13 13:58 o1_mf_nnndf_TAG20160413T142516_cjvtrp7p_.bkp
-rw-r----- 1 oratest oratest 1105920 Apr 13 13:58 o1_mf_nnndf_TAG20160413T142516_cjvtrxhf_.bkp
-rw-r----- 1 oratest oratest 1753088 Apr 13 13:58 o1_mf_nnndf_TAG20160413T142516_cjvts0wr_.bkp
-rw-r----- 1 oratest oratest 12312576 Apr 13 13:58 o1_mf_nnndf_TAG20160413T142516_cjvts2b7_.bkp
-rw-r----- 1 oratest oratest 380239872 Apr 13 14:01 o1_mf_nnndf_TAG20160413T142516_cjvts9w8_.bkp
-rw-r----- 1 oratest oratest 1277952 Apr 13 14:01 o1_mf_nnndf_TAG20160413T142516_cjvtyh70_.bkp
-rw-r----- 1 oratest oratest 1114112 Apr 13 14:01 o1_mf_nnndf_TAG20160413T142516_cjvtypkv_.bkp
-rw-r----- 1 oratest oratest 24395776 Apr 13 14:02 o1_mf_nnndf_TAG20160413T142516_cjvtyqxp_.bkp
-rw-r----- 1 oratest oratest 2891776 Apr 13 14:02 o1_mf_nnndf_TAG20160413T142516_cjvtzkfw_.bkp
-rw-r----- 1 oratest oratest 1130496 Apr 13 14:02 o1_mf_nnndf_TAG20160413T142516_cjvtzrlc_.bkp
-rw-r----- 1 oratest oratest 2410258432 Apr 13 14:03 o1_mf_nnndf_TAG20160413T142516_cjvt6s11_.bkp
testdbdev:TESTDB:/dbfra/testdbdev/TESTDB/backupset/2016_04_13> ls -lrt *T142516* |wc -l
21
testdbdev:TESTDB:/dbfra/testdbdev/TESTDB/backupset/2016_04_13> ls -lrt *T142516* |awk '{ sum += $5 } END { print sum }'
5343789056
It is about 5.3GB.
--this is the level 0 created by very first level 1
testdbdev:TESTDB:/dbfra/testdbdev/TESTDB/backupset/2016_04_13> ls -lrt *T150822*
-rw-r----- 1 oratest oratest 9838592 Apr 13 14:27 o1_mf_nnnd1_TAG20160413T150822_cjvw37f7_.bkp
-rw-r----- 1 oratest oratest 10159611904 Apr 13 15:41 o1_mf_nnnd1_TAG20160413T150822_cjvw37f2_.bkp
-rw-r----- 1 oratest oratest 8804286464 Apr 13 15:41 o1_mf_nnnd1_TAG20160413T150822_cjvwgz4w_.bkp
-rw-r----- 1 oratest oratest 403144704 Apr 13 15:49 o1_mf_nnnd1_TAG20160413T150822_cjw0swgl_.bkp
-rw-r----- 1 oratest oratest 3922280448 Apr 13 16:11 o1_mf_nnnd1_TAG20160413T150822_cjw0s379_.bkp
-rw-r----- 1 oratest oratest 1470185472 Apr 13 16:23 o1_mf_nnnd1_TAG20160413T150822_cjw2l7bw_.bkp
-rw-r----- 1 oratest oratest 4727996416 Apr 13 16:23 o1_mf_nnnd1_TAG20160413T150822_cjw18rk1_.bkp
-rw-r----- 1 oratest oratest 234045440 Apr 13 16:24 o1_mf_nnnd0_TAG20160413T150822_cjw38mvs_.bkp
-rw-r----- 1 oratest oratest 1351680 Apr 13 16:25 o1_mf_nnnd1_TAG20160413T150822_cjw3c67g_.bkp
-rw-r----- 1 oratest oratest 2703360 Apr 13 16:26 o1_mf_nnnd1_TAG20160413T150822_cjw3dxqy_.bkp
-rw-r----- 1 oratest oratest 2056192 Apr 13 16:27 o1_mf_nnnd1_TAG20160413T150822_cjw3gofy_.bkp
-rw-r----- 1 oratest oratest 2482176 Apr 13 16:27 o1_mf_nnnd1_TAG20160413T150822_cjw3j2co_.bkp
-rw-r----- 1 oratest oratest 16982016 Apr 13 16:28 o1_mf_nnnd1_TAG20160413T150822_cjw3jkmp_.bkp
-rw-r----- 1 oratest oratest 527409152 Apr 13 16:28 o1_mf_nnnd1_TAG20160413T150822_cjw38tpx_.bkp
-rw-r----- 1 oratest oratest 16621568 Apr 13 16:28 o1_mf_nnnd1_TAG20160413T150822_cjw3kbwl_.bkp
-rw-r----- 1 oratest oratest 27369472 Apr 13 16:28 o1_mf_nnnd1_TAG20160413T150822_cjw3klhk_.bkp
-rw-r----- 1 oratest oratest 1302528 Apr 13 16:28 o1_mf_nnnd1_TAG20160413T150822_cjw3l2fo_.bkp
-rw-r----- 1 oratest oratest 1114112 Apr 13 16:29 o1_mf_nnnd1_TAG20160413T150822_cjw3lk6v_.bkp
-rw-r----- 1 oratest oratest 2875392 Apr 13 16:29 o1_mf_nnnd1_TAG20160413T150822_cjw3m43h_.bkp
-rw-r----- 1 oratest oratest 1081344 Apr 13 16:29 o1_mf_nnnd1_TAG20160413T150822_cjw3mmb2_.bkp
-rw-r----- 1 oratest oratest 141950976 Apr 13 16:29 o1_mf_nnnd0_TAG20160413T150822_cjw3lnyk_.bkp
testdbdev:TESTDB:/dbfra/testdbdev/TESTDB/backupset/2016_04_13> ls -lrt *T150822* |wc -l
21
testdbdev:TESTDB:/dbfra/testdbdev/TESTDB/backupset/2016_04_13> ls -lrt *T150822* | awk '{ sum += $5 } END { print sum }'
30476689408
The size is about 30GB.
Duration for this run is about 102 minutes.
-- run a level 0 backup using command "BACKUP filesperset 2 incremental level 0 DATABASE ;"
testdb01:EDWD:/dbfra/testdb01/EDWD/backupset/2016_04_13> ls -lrt *T173009* |wc -l
21
testdb01:EDWD:/dbfra/testdb01/EDWD/backupset/2016_04_13> ls -lrt *T173009*
-rw-r----- 1 oratest oratest 38264832 Apr 13 16:43 o1_mf_nnnd0_TAG20160413T173009_cjw4f3hk_.bkp
-rw-r----- 1 oratest oratest 8224768 Apr 13 16:45 o1_mf_nnnd0_TAG20160413T173009_cjw4f3t3_.bkp
-rw-r----- 1 oratest oratest 2203648 Apr 13 16:45 o1_mf_nnnd0_TAG20160413T173009_cjw4jx5z_.bkp
-rw-r----- 1 oratest oratest 17235968 Apr 13 16:46 o1_mf_nnnd0_TAG20160413T173009_cjw4l0xx_.bkp
-rw-r----- 1 oratest oratest 18685952 Apr 13 16:46 o1_mf_nnnd0_TAG20160413T173009_cjw4ltlb_.bkp
-rw-r----- 1 oratest oratest 1310720 Apr 13 16:47 o1_mf_nnnd0_TAG20160413T173009_cjw4n8d9_.bkp
-rw-r----- 1 oratest oratest 2809856 Apr 13 16:48 o1_mf_nnnd0_TAG20160413T173009_cjw4ooqv_.bkp
-rw-r----- 1 oratest oratest 2097152 Apr 13 16:48 o1_mf_nnnd0_TAG20160413T173009_cjw4qfgm_.bkp
-rw-r----- 1 oratest oratest 1105920 Apr 13 16:48 o1_mf_nnnd0_TAG20160413T173009_cjw4qwvk_.bkp
-rw-r----- 1 oratest oratest 1753088 Apr 13 16:48 o1_mf_nnnd0_TAG20160413T173009_cjw4r4jj_.bkp
-rw-r----- 1 oratest oratest 12312576 Apr 13 16:49 o1_mf_nnnd0_TAG20160413T173009_cjw4r7wf_.bkp
-rw-r----- 1 oratest oratest 8839168 Apr 13 16:50 o1_mf_nnnd0_TAG20160413T173009_cjw4f37p_.bkp
-rw-r----- 1 oratest oratest 37568512 Apr 13 16:51 o1_mf_nnnd0_TAG20160413T173009_cjw4f4d1_.bkp
-rw-r----- 1 oratest oratest 1114112 Apr 13 16:51 o1_mf_nnnd0_TAG20160413T173009_cjw4w1t9_.bkp
-rw-r----- 1 oratest oratest 1277952 Apr 13 16:51 o1_mf_nnnd0_TAG20160413T173009_cjw4w1bb_.bkp
-rw-r----- 1 oratest oratest 2891776 Apr 13 16:51 o1_mf_nnnd0_TAG20160413T173009_cjw4wc9q_.bkp
-rw-r----- 1 oratest oratest 1130496 Apr 13 16:51 o1_mf_nnnd0_TAG20160413T173009_cjw4wlqb_.bkp
-rw-r----- 1 oratest oratest 24395776 Apr 13 16:51 o1_mf_nnnd0_TAG20160413T173009_cjw4w3l3_.bkp
-rw-r----- 1 oratest oratest 380403712 Apr 13 16:52 o1_mf_nnnd0_TAG20160413T173009_cjw4rqrp_.bkp
-rw-r----- 1 oratest oratest 2410258432 Apr 13 17:02 o1_mf_nnnd0_TAG20160413T173009_cjw4gvf8_.bkp
-rw-r----- 1 oratest oratest 2370019328 Apr 13 17:04 o1_mf_nnnd0_TAG20160413T173009_cjw4f38v_.bkp
testdb01:EDWD:/dbfra/testdb01/EDWD/backupset/2016_04_13> ls -lrt *T173009* | awk '{ sum += $5 } END { print sum }'
5343903744
The size is 5.3GB. The duration is about 22 minutes.
I have tested twice for this finding to support my conclusion. Interesting and can someone explains? Thanks.
