[20190510]rman备份的疑问8.txt

[20190510]rman备份的疑问8.txt

--//上午测试rman备份多个文件,探究input memory buffer 的问题.
--//补充测试5个文件的情况.
--//http://blog.itpub.net/267265/viewspace-2148246/=>[20171204]关于rman备份疑问4.txt

1.环境:
SCOTT@book> @ ver1
PORT_STRING                    VERSION        BANNER
------------------------------ -------------- --------------------------------------------------------------------------------
x86_64/Linux 2.4.xx            11.2.0.4.0     Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production

$ cat dx.sql
drop tablespace t&1 including contents and datafiles;
CREATE TABLESPACE T&1 DATAFILE '/mnt/ramdisk/book/T&1..dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;
create table t&1 tablespace t&1 as select rownum id ,to_char(rownum,'FM000000')||lpad('&&2',26,'&&2') name from dual connect by level<=1e5;
--//T&1..dbf 2个点.事后才发现这个小问题.

$ paste -d " " <(seq -f "%02g" 5 ) <((echo A B C D E | tr ' ' '\n' )) | xargs -IQ echo @ dx Q | sqlplus -s -l scott/book

2.修改rman配置:

RMAN> CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 128 K;
using target database control file instead of recovery catalog
old RMAN configuration parameters:
CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 512 K;
new RMAN configuration parameters:
CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 128 K;
new RMAN configuration parameters are successfully stored
--//延迟备份写盘速度,就可以看出一些细节.

--//RMAN> CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET;
--//RMAN> CONFIGURE CONTROLFILE AUTOBACKUP OFF;

3.备份:
RMAN> backup  datafile 9,10,11,12,13 format '/home/oracle/backup/t12345_%t_%U' ;

Starting backup at 2019-05-10 17:16:28
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=58 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=00009 name=/mnt/ramdisk/book/T01dbf
input datafile file number=00010 name=/mnt/ramdisk/book/T02dbf
input datafile file number=00011 name=/mnt/ramdisk/book/T03dbf
input datafile file number=00012 name=/mnt/ramdisk/book/T04dbf
input datafile file number=00013 name=/mnt/ramdisk/book/T05dbf
channel ORA_DISK_1: starting piece 1 at 2019-05-10 17:16:28
channel ORA_DISK_1: finished piece 1 at 2019-05-10 17:20:33
piece handle=/home/oracle/backup/t12345_1007918188_2ju1773c_1_1 tag=TAG20190510T171628 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:04:05
channel ORA_DISK_1: throttle time: 0:04:00
Finished backup at 2019-05-10 17:20:33

--//执行如下:
SELECT set_count
        ,device_type
        ,TYPE
        ,filename
        ,buffer_size
        ,buffer_count
        ,open_time
        ,close_time
    FROM v$backup_async_io
   where set_count=83
ORDER BY set_count
        ,TYPE
        ,open_time
        ,close_time;

SET_COUNT DEVICE_TYPE TYPE      FILENAME                                           BUFFER_SIZE BUFFER_COUNT OPEN_TIME           CLOSE_TIME
--------- ----------- --------- -------------------------------------------------- ----------- ------------ ------------------- -------------------
       83 DISK        AGGREGATE                                                              0            0 2019-05-10 17:16:28 2019-05-10 17:20:28
       83 DISK        INPUT     /mnt/ramdisk/book/T01dbf                                524288            6 2019-05-10 17:16:28 2019-05-10 17:20:28
       83 DISK        INPUT     /mnt/ramdisk/book/T02dbf                                524288            6 2019-05-10 17:16:28 2019-05-10 17:20:28
       83 DISK        INPUT     /mnt/ramdisk/book/T03dbf                                524288            6 2019-05-10 17:16:32 2019-05-10 17:20:28
       83 DISK        INPUT     /mnt/ramdisk/book/T04dbf                                524288            6 2019-05-10 17:16:36 2019-05-10 17:20:28
       83 DISK        INPUT     /mnt/ramdisk/book/T05dbf                                524288            6 2019-05-10 17:16:40 2019-05-10 17:20:28
       83 DISK        OUTPUT    /home/oracle/backup/t12345_1007918188_2ju1773c_1_1     1048576            4 2019-05-10 17:16:28 2019-05-10 17:20:28
7 rows selected.
--//注意看OPEN_TIME的时间,间隔4秒.顺序启动读取T03,T04,T05.
--//单个输入缓存512K ,512*6=3M.
--//开始启动同时读取T01,T02
--//也就是写出512K时,开始读取T03.再写出512K,读取T04.再再写出512K时,读取T05.
--//而512K就是一个input buffer 的大小,也就是开始阶段写完1个input buffer到output buffer,读取新数据文件.

4.如果我验证备份时3个文件,T03读取是8秒以后就可以验证我的判断.

RMAN> backup  datafile 9,10,11 format '/home/oracle/backup/t1_%t_%U' ;
Starting backup at 2019-05-10 17:28:09
using channel ORA_DISK_1
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00009 name=/mnt/ramdisk/book/T01dbf
input datafile file number=00010 name=/mnt/ramdisk/book/T02dbf
input datafile file number=00011 name=/mnt/ramdisk/book/T03dbf
channel ORA_DISK_1: starting piece 1 at 2019-05-10 17:28:09
channel ORA_DISK_1: finished piece 1 at 2019-05-10 17:30:34
piece handle=/home/oracle/backup/t1_1007918889_2mu177p9_1_1 tag=TAG20190510T172809 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:02:25
channel ORA_DISK_1: throttle time: 0:02:24
Finished backup at 2019-05-10 17:30:34

SELECT set_count
        ,device_type
        ,TYPE
        ,filename
        ,buffer_size
        ,buffer_count
        ,open_time
        ,close_time
    FROM v$backup_async_io
   where set_count=86
ORDER BY set_count
        ,TYPE
        ,open_time
        ,close_time;

SET_COUNT DEVICE_TYPE TYPE      FILENAME                                       BUFFER_SIZE BUFFER_COUNT OPEN_TIME           CLOSE_TIME
--------- ----------- --------- ---------------------------------------------- ----------- ------------ ------------------- -------------------
       86 DISK        AGGREGATE                                                          0            0 2019-05-10 17:28:09 2019-05-10 17:30:33
       86 DISK        INPUT     /mnt/ramdisk/book/T01dbf                           1048576            5 2019-05-10 17:28:09 2019-05-10 17:30:33
       86 DISK        INPUT     /mnt/ramdisk/book/T02dbf                           1048576            5 2019-05-10 17:28:09 2019-05-10 17:30:33
       86 DISK        INPUT     /mnt/ramdisk/book/T03dbf                           1048576            5 2019-05-10 17:28:17 2019-05-10 17:30:33
       86 DISK        OUTPUT    /home/oracle/backup/t1_1007918889_2mu177p9_1_1     1048576            4 2019-05-10 17:28:09 2019-05-10 17:30:33

--//注意看OPEN_TIME的时间,间隔8秒.启动读取T03.
--//单个输入缓存1024K ,1024*5=3M.
--//开始启动同时读取T01,T02
--//也就是写出1M时,开始读取T03.
--//而1024K就是一个input buffer 的大小,也就是开始阶段写完1个input buffer到output buffer,读取新数据文件.

--//贴出4个文件的情况:
RMAN> backup  datafile 9,10,11,12 format '/home/oracle/backup/t1_%t_%U' ;
Starting backup at 2019-05-10 17:35:43
using channel ORA_DISK_1
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00009 name=/mnt/ramdisk/book/T01dbf
input datafile file number=00010 name=/mnt/ramdisk/book/T02dbf
input datafile file number=00011 name=/mnt/ramdisk/book/T03dbf
input datafile file number=00012 name=/mnt/ramdisk/book/T04dbf
channel ORA_DISK_1: starting piece 1 at 2019-05-10 17:35:43
channel ORA_DISK_1: finished piece 1 at 2019-05-10 17:38:58
piece handle=/home/oracle/backup/t1_1007919343_2nu1787f_1_1 tag=TAG20190510T173543 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:03:15
channel ORA_DISK_1: throttle time: 0:03:12
Finished backup at 2019-05-10 17:38:58

SET_COUNT DEVICE_TYPE TYPE      FILENAME                                           BUFFER_SIZE BUFFER_COUNT OPEN_TIME           CLOSE_TIME
--------- ----------- --------- -------------------------------------------------- ----------- ------------ ------------------- -------------------
       87 DISK        AGGREGATE                                                              0            0 2019-05-10 17:35:43 2019-05-10 17:38:55
       87 DISK        INPUT     /mnt/ramdisk/book/T01dbf                               1048576            4 2019-05-10 17:35:43 2019-05-10 17:38:55
       87 DISK        INPUT     /mnt/ramdisk/book/T02dbf                               1048576            4 2019-05-10 17:35:43 2019-05-10 17:38:55
       87 DISK        INPUT     /mnt/ramdisk/book/T03dbf                               1048576            4 2019-05-10 17:35:51 2019-05-10 17:38:55
       87 DISK        INPUT     /mnt/ramdisk/book/T04dbf                               1048576            4 2019-05-10 17:35:59 2019-05-10 17:38:55
       87 DISK        OUTPUT    /home/oracle/backup/t1_1007919343_2nu1787f_1_1         1048576            4 2019-05-10 17:35:43 2019-05-10 17:38:55
6 rows selected.
--//自己看,不再解析了.


[20190510]rman备份的疑问8.txt

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