[20190510]rman备份的疑问8.txt

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[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.