[20171129]rman input memory buffer 5.txt-白红宇

[20171129]rman input memory buffer 5.txt

--//Input Memory Buffers如何测试,不清楚.不过找到一本电子书.摘要如下:

Oracle RMAN 11g Backup and Recovery.pdf

作者:Robert G. Freeman Matthew Hart

页数:689

出版社:Mc graw hill

出版号: ISBN: 978-0-07-162861-7

MHID: 0-07-162861-4

RMAN in Memory P80

RMAN builds buffers in memory through which it streams data blocks for potential backup. This

memory utilization counts against the total size of the PGA and, sometimes, the SGA. There are

two kinds of memory buffers. Input buffers are the buffers that are filled with data blocks read

from files that are being backed up. Output buffers are the buffers that are filled when the

memory-to-memory write occurs to determine whether a particular block needs to be backed up.

When the output buffer is filled, it is written to the backup location. The memory buffers differ

depending on whether you are backing up to or restoring from disk or tape. Figure 2-3 illustrates

input and output buffer allocation. It illustrates a backup of two datafiles being multiplexed into

a single backup set.

Input Memory Buffers

When you are backing up the database, the size and number of input memory buffers depend on

the exact backup command being executed. Primarily, they depend on the number of files being

multiplexed into a single backup. Multiplexing refers to the number of files that will have their

blocks backed up to the same backup piece. To keep the memory allocation within reason, the

following rules are applied to the memory buffer sizes based on the number of files being backed

up together:

■ If the number of files going into the backup set is four or less, then RMAN allocates four

buffers per file at 1MB per buffer. The total will be 16MB or less.

■ If the number of files going into the backup set is greater than four, but no greater than

eight, then each file gets four buffers, each of 512KB. This ensures that the total remains

at 16MB or less.

■ If the number of files being multiplexed is greater than eight, then RMAN allocates four

buffers of size 128KB. This ensures that each file being backed up will account for 512KB

of buffer memory.

--//可以想像如果输入缓存如果全部写入输出缓存,通过输出文件写到备份集中的数据分布,也能猜测出输入缓存大小.

--//补充测试10个数据文件作为1个备份集合的情况:(11G的情况)

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

CREATE TABLESPACE T01 DATAFILE '/mnt/ramdisk/book/T01.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T02 DATAFILE '/mnt/ramdisk/book/T02.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T03 DATAFILE '/mnt/ramdisk/book/T03.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T04 DATAFILE '/mnt/ramdisk/book/T04.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T05 DATAFILE '/mnt/ramdisk/book/T05.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T06 DATAFILE '/mnt/ramdisk/book/T06.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T07 DATAFILE '/mnt/ramdisk/book/T07.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T08 DATAFILE '/mnt/ramdisk/book/T08.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T09 DATAFILE '/mnt/ramdisk/book/T09.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

CREATE TABLESPACE T10 DATAFILE '/mnt/ramdisk/book/T10.dbf' SIZE 6M AUTOEXTEND OFF LOGGING ONLINE EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 8K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON;

create table t01 tablespace t01 as select rownum id ,lpad('A',32,'A') name from dual connect by level<=1e5;

create table t02 tablespace t02 as select rownum id ,lpad('B',32,'B') name from dual connect by level<=1e5;

create table t03 tablespace t03 as select rownum id ,lpad('C',32,'C') name from dual connect by level<=1e5;

create table t04 tablespace t04 as select rownum id ,lpad('D',32,'D') name from dual connect by level<=1e5;

create table t05 tablespace t05 as select rownum id ,lpad('E',32,'E') name from dual connect by level<=1e5;

create table t06 tablespace t06 as select rownum id ,lpad('F',32,'F') name from dual connect by level<=1e5;

create table t07 tablespace t07 as select rownum id ,lpad('G',32,'G') name from dual connect by level<=1e5;

create table t08 tablespace t08 as select rownum id ,lpad('H',32,'H') name from dual connect by level<=1e5;

create table t09 tablespace t09 as select rownum id ,lpad('I',32,'I') name from dual connect by level<=1e5;

create table t10 tablespace t10 as select rownum id ,lpad('J',32,'J') name from dual connect by level<=1e5;

alter system checkpoint;

2.测试备份的情况:

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

RMAN> CONFIGURE CHANNEL 1 DEVICE TYPE DISK CLEAR;

old RMAN configuration parameters:

CONFIGURE CHANNEL 1 DEVICE TYPE DISK RATE 128 K;

old RMAN configuration parameters are successfully deleted

--//前面的测试限速取消.

RMAN> report schema;

Report of database schema for database with db_unique_name BOOK

List of Permanent Datafiles

===========================

File Size(MB) Tablespace RB segs Datafile Name

---- -------- -------------------- ------- ------------------------

1 760 SYSTEM *** /mnt/ramdisk/book/system01.dbf

2 940 SYSAUX *** /mnt/ramdisk/book/sysaux01.dbf

3 1075 UNDOTBS1 *** /mnt/ramdisk/book/undotbs01.dbf

4 2166 USERS *** /mnt/ramdisk/book/users01.dbf

5 346 EXAMPLE *** /mnt/ramdisk/book/example01.dbf

6 42 TEA *** /mnt/ramdisk/book/tea01.dbf

7 6 T01 *** /mnt/ramdisk/book/T01.dbf

8 6 T02 *** /mnt/ramdisk/book/T02.dbf

9 6 T03 *** /mnt/ramdisk/book/T03.dbf

10 6 T04 *** /mnt/ramdisk/book/T04.dbf

11 6 T05 *** /mnt/ramdisk/book/T05.dbf

12 6 T06 *** /mnt/ramdisk/book/T06.dbf

13 6 T07 *** /mnt/ramdisk/book/T07.dbf

14 6 T08 *** /mnt/ramdisk/book/T08.dbf

15 6 T09 *** /mnt/ramdisk/book/T09.dbf

16 6 T10 *** /mnt/ramdisk/book/T10.dbf

List of Temporary Files

=======================

File Size(MB) Tablespace Maxsize(MB) Tempfile Name

---- -------- -------------------- ----------- --------------------

1 414 TEMP 32767 /mnt/ramdisk/book/temp01.dbf

RMAN> backup datafile 7,8,9,10,11,12,13,14,15,16 filesperset 10 format '/home/oracle/backup/t123456789A_%U';

Starting backup at 2017-11-29 11:11:50

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=00007 name=/mnt/ramdisk/book/T01.dbf

input datafile file number=00008 name=/mnt/ramdisk/book/T02.dbf

input datafile file number=00009 name=/mnt/ramdisk/book/T03.dbf

input datafile file number=00010 name=/mnt/ramdisk/book/T04.dbf

input datafile file number=00011 name=/mnt/ramdisk/book/T05.dbf

input datafile file number=00012 name=/mnt/ramdisk/book/T06.dbf

input datafile file number=00013 name=/mnt/ramdisk/book/T07.dbf

input datafile file number=00014 name=/mnt/ramdisk/book/T08.dbf

input datafile file number=00015 name=/mnt/ramdisk/book/T09.dbf

input datafile file number=00016 name=/mnt/ramdisk/book/T10.dbf

channel ORA_DISK_1: starting piece 1 at 2017-11-29 11:11:50

channel ORA_DISK_1: finished piece 1 at 2017-11-29 11:11:51

piece handle=/home/oracle/backup/t123456789A_m8skpbjm_1_1 tag=TAG20171129T111150 comment=NONE

channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01

Finished backup at 2017-11-29 11:11:51

Starting Control File and SPFILE Autobackup at 2017-11-29 11:11:51

piece handle=/u01/app/oracle/fast_recovery_area/BOOK/autobackup/2017_11_29/o1_mf_s_961326711_f1w9cqhz_.bkp comment=NONE

Finished Control File and SPFILE Autobackup at 2017-11-29 11:11:52

9978 AAAAAAAAAA

9978 BBBBBBBBBB

9978 CCCCCCCCCC

9978 DDDDDDDDDD

9978 EEEEEEEEEE

9978 FFFFFFFFFF

9978 GGGGGGGGGG

9978 HHHHHHHHHH

10080 AAAAAAAAAA

10080 BBBBBBBBBB

10080 CCCCCCCCCC

10080 DDDDDDDDDD

10080 EEEEEEEEEE

10080 FFFFFFFFFF

10080 GGGGGGGGGG

10080 HHHHHHHHHH

10416 AAAAAAAAAA

10416 BBBBBBBBBB

10416 CCCCCCCCCC

10416 DDDDDDDDDD

10416 EEEEEEEEEE

10416 FFFFFFFFFF

10416 GGGGGGGGGG

10416 HHHHHHHHHH

10752 AAAAAAAAAA

10752 BBBBBBBBBB

10752 CCCCCCCCCC

10752 DDDDDDDDDD

10752 EEEEEEEEEE

10752 FFFFFFFFFF

10752 GGGGGGGGGG

10752 HHHHHHHHHH

10416 AAAAAAAAAA

10416 BBBBBBBBBB

10416 CCCCCCCCCC

10416 DDDDDDDDDD

10416 EEEEEEEEEE

10416 FFFFFFFFFF

10416 GGGGGGGGGG

10416 HHHHHHHHHH

10752 AAAAAAAAAA

10752 BBBBBBBBBB

10752 CCCCCCCCCC

10752 DDDDDDDDDD

10752 EEEEEEEEEE

10752 FFFFFFFFFF

10752 GGGGGGGGGG

10752 HHHHHHHHHH

10416 AAAAAAAAAA

10416 BBBBBBBBBB

10416 CCCCCCCCCC

10416 DDDDDDDDDD

10416 EEEEEEEEEE

10416 FFFFFFFFFF

10416 GGGGGGGGGG

10416 HHHHHHHHHH

10752 AAAAAAAAAA

10752 BBBBBBBBBB

10752 CCCCCCCCCC

10752 DDDDDDDDDD

10752 EEEEEEEEEE

10752 FFFFFFFFFF

10752 GGGGGGGGGG

10752 HHHHHHHHHH

10416 AAAAAAAAAA

10416 BBBBBBBBBB

10416 CCCCCCCCCC

10416 DDDDDDDDDD

10416 EEEEEEEEEE

10416 FFFFFFFFFF

10416 GGGGGGGGGG

10416 HHHHHHHHHH

6022 AAAAAAAAAA

6022 BBBBBBBBBB

6022 CCCCCCCCCC

6022 DDDDDDDDDD

6022 EEEEEEEEEE

6022 FFFFFFFFFF

6022 GGGGGGGGGG

6022 HHHHHHHHHH

---//前解决8个数据文件

9978 IIIIIIIIII

9978 JJJJJJJJJJ

10080 IIIIIIIIII

10080 JJJJJJJJJJ

10416 IIIIIIIIII

10416 JJJJJJJJJJ

10752 IIIIIIIIII

10752 JJJJJJJJJJ

10416 IIIIIIIIII

10416 JJJJJJJJJJ

10752 IIIIIIIIII

10752 JJJJJJJJJJ

10416 IIIIIIIIII

10416 JJJJJJJJJJ

10752 IIIIIIIIII

10752 JJJJJJJJJJ

10416 IIIIIIIIII

10416 JJJJJJJJJJ

6022 IIIIIIIIII

6022 JJJJJJJJJJ

--//备份集合大于8个,先备份8个数据文件,输入缓存512K.继续解决...,如此循环.

--//不过从数量上看读512K(64块)