[20171128]rman Input or output Memory Buffers.txt
--//做一个简单测试rman 的Input or output Memory Buffers.
1.环境:
SCOTT@book> @ &r/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
--// drop tablespace sugar including contents and datafiles;
CREATE TABLESPACE SUGAR DATAFILE
'/mnt/ramdisk/book/sugar01.dbf' SIZE 11M AUTOEXTEND OFF
LOGGING
ONLINE
EXTENT MANAGEMENT LOCAL AUTOALLOCATE
BLOCKSIZE 8K
SEGMENT SPACE MANAGEMENT AUTO
FLASHBACK ON;
create table t1 tablespace sugar as select rownum id ,lpad('A',32,'A') name from dual connect by level<=2e5;
SCOTT@book> select sum(bytes) from dba_extents where owner=user and segment_name in ('T1');
SUM(BYTES)
----------
10485760
--//rman配置:
RMAN> CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 128k;
new RMAN configuration parameters:
CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 128 K;
new RMAN configuration parameters are successfully stored
RMAN> CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET;
old RMAN configuration parameters:
CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET;
new RMAN configuration parameters:
CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET;
new RMAN configuration parameters are successfully stored
--//建立测试脚本.
$ cat out.sh
#!/bin/bash
rman target / <<EOF &
backup as copy datafile 7 format '/home/oracle/backup/%b_1' ;
EOF
for i in {1..100}
do
echo -n $(date +%H%M%S) ":" >> /tmp/aaa.txt
strings /home/oracle/backup/sugar01.dbf_1 2>/dev/null | grep "AAAAA" |wc >> /tmp/aaa.txt 2>/dev/null
sleep 1
done
2.做表空间sugar的映像备份:
$ . out.sh
....
Starting backup at 2017-11-28 15:09:25
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=144 device type=DISK
channel ORA_DISK_1: starting datafile copy
input datafile file number=00007 name=/mnt/ramdisk/book/sugar01.dbf
output file name=/home/oracle/backup/sugar01.dbf_1 tag=TAG20171128T150925 RECID=69 STAMP=961254653
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:01:35
channel ORA_DISK_1: throttle time: 0:01:28
Finished backup at 2017-11-28 15:11:00
Starting Control File and SPFILE Autobackup at 2017-11-28 15:11:00
piece handle=/u01/app/oracle/fast_recovery_area/BOOK/autobackup/2017_11_28/o1_mf_s_961254660_f1t304tk_.bkp comment=NONE
Finished Control File and SPFILE Autobackup at 2017-11-28 15:11:01
....
$ cut -d":" -f2 /tmp/aaa.txt | uniq -c
9 0 0 0
6 20058 34093 725881
6 41226 70058 1491458
7 62394 106045 2256986
6 83562 142017 3023196
6 104730 178013 3794099
6 125898 214038 4560480
6 147066 250034 5326802
6 168234 286030 6093124
6 189402 322053 6859500
36 200000 340080 7243181
--//可以发现前9秒没有AAAA.
$ time strings /home/oracle/backup/sugar01.dbf_1 2>/dev/null | grep "AAAAA" |wc
200000 340080 7243181
real 0m0.336s
user 0m0.410s
sys 0m0.032s
--//单独执行strings消耗.0410s.这样6次,strings大约消耗2.4秒.这样大约8秒,AAAA的次数就发生变化.
--//而CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 128k;这样1M数据量就需要8秒.
--//另外还可以看出前后相减:
20058 - 0 = 20058
41226 - 20058 = 21168
62394 - 41226 = 21168
83562 - 62394 = 21168
104730 - 83562 = 21168
125898 -104730 = 21168
147066 -125898 = 21168
168234 -147066 = 21168
189402 -168234 = 21168
--//除了第1个数量是20058外,其它都是21168.
SCOTT@book> column PARTITION_NAME noprint
SCOTT@book> select * from dba_extents where segment_name='T1';
OWNER SEGMENT_NAME SEGMENT_TYPE TABLESPACE_NAME EXTENT_ID FILE_ID BLOCK_ID BYTES BLOCKS RELATIVE_FNO
------ ------------ ------------ --------------- ---------- ---------- ---------- ---------- ---------- ------------
SCOTT T1 TABLE SUGAR 0 7 128 65536 8 7
SCOTT T1 TABLE SUGAR 1 7 136 65536 8 7
SCOTT T1 TABLE SUGAR 2 7 144 65536 8 7
SCOTT T1 TABLE SUGAR 3 7 152 65536 8 7
SCOTT T1 TABLE SUGAR 4 7 160 65536 8 7
SCOTT T1 TABLE SUGAR 5 7 168 65536 8 7
SCOTT T1 TABLE SUGAR 6 7 176 65536 8 7
SCOTT T1 TABLE SUGAR 7 7 184 65536 8 7
SCOTT T1 TABLE SUGAR 8 7 192 65536 8 7
SCOTT T1 TABLE SUGAR 9 7 200 65536 8 7
SCOTT T1 TABLE SUGAR 10 7 208 65536 8 7
SCOTT T1 TABLE SUGAR 11 7 216 65536 8 7
SCOTT T1 TABLE SUGAR 12 7 224 65536 8 7
SCOTT T1 TABLE SUGAR 13 7 232 65536 8 7
SCOTT T1 TABLE SUGAR 14 7 240 65536 8 7
SCOTT T1 TABLE SUGAR 15 7 248 65536 8 7
SCOTT T1 TABLE SUGAR 16 7 256 1048576 128 7
SCOTT T1 TABLE SUGAR 17 7 384 1048576 128 7
SCOTT T1 TABLE SUGAR 18 7 512 1048576 128 7
SCOTT T1 TABLE SUGAR 19 7 640 1048576 128 7
SCOTT T1 TABLE SUGAR 20 7 768 1048576 128 7
SCOTT T1 TABLE SUGAR 21 7 896 1048576 128 7
SCOTT T1 TABLE SUGAR 22 7 1024 1048576 128 7
SCOTT T1 TABLE SUGAR 23 7 1152 1048576 128 7
SCOTT T1 TABLE SUGAR 24 7 1280 1048576 128 7
25 rows selected.
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 128 and 256-1;
COUNT(*)
----------
20058
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 256 and 384-1;
COUNT(*)
----------
21168
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 384 and 512-1;
COUNT(*)
----------
21168
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 512 and 640-1;
COUNT(*)
----------
21168
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 640 and 768-1;
COUNT(*)
----------
21168
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 768 and 896-1;
COUNT(*)
----------
21168
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 896 and 1024-1;
COUNT(*)
----------
21168
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 1024 and 1152-1;
COUNT(*)
----------
21168
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 1152 and 1280-1;
COUNT(*)
----------
21168
SCOTT@book> select count(*) from t1 where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) >= 1280 ;
COUNT(*)
----------
10598
--//8*21168+20058=189402
--//189402+10598=200000
--//说明oracle 的输出缓存是1M.
--//你可能认为不是顺序读取.
--//修改一定的记录看看.
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 128 and 256-1 and rownum<=1;
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 256 and 384-1 and rownum<=2;
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 384 and 512-1 and rownum<=3;
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 512 and 640-1 and rownum<=4;
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 640 and 768-1 and rownum<=5;
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 768 and 896-1 and rownum<=6;
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 896 and 1024-1 and rownum<=7;
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 1024 and 1152-1 and rownum<=8;
update t1 set name=lpad('B',32,'B') where DBMS_ROWID.ROWID_BLOCK_NUMBER (rowid) between 1152 and 1280-1 and rownum<=9;
commit;
alter system checkpoint;
alter system checkpoint;
alter system checkpoint;
$ cat out1.sh
#!/bin/bash
rman target / <<EOF &
backup as copy datafile 7 format '/home/oracle/backup/%b_1' ;
EOF
for i in {1..100}
do
echo -n $(date +%H%M%S-%N) ":" >> /tmp/aaa.txt
strings /home/oracle/backup/sugar01.dbf_1 2>/dev/null | grep "BBBBB" |wc >> /tmp/aaa.txt 2>/dev/null
sleep 1
done
$ . out1.sh
....
Starting backup at 2017-11-28 15:22:35
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=132 device type=DISK
channel ORA_DISK_1: starting datafile copy
input datafile file number=00007 name=/mnt/ramdisk/book/sugar01.dbf
output file name=/home/oracle/backup/sugar01.dbf_1 tag=TAG20171128T152235 RECID=70 STAMP=961255443
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:01:35
channel ORA_DISK_1: throttle time: 0:01:28
Finished backup at 2017-11-28 15:24:10
Starting Control File and SPFILE Autobackup at 2017-11-28 15:24:10
piece handle=/u01/app/oracle/fast_recovery_area/BOOK/autobackup/2017_11_28/o1_mf_s_961255450_f1t3rtys_.bkp comment=NONE
Finished Control File and SPFILE Autobackup at 2017-11-28 15:24:11
...
$ cut -d":" -f2 /tmp/aaa.txt | uniq -c
9 0 0 0
6 1 1 34
6 3 5 105
7 6 8 209
6 10 16 352
6 15 26 541
7 21 38 762
6 28 47 1009
6 36 63 1304
30 45 81 1636
--//前后相减正好是1,2,3,4,5,6,7,8,9.不正说明是顺序读取的吗?
--//没有测试input memory buffer.有点长,另外写一篇.
