我们将尝试找出文件的AU分布,然后根据AU分布定位磁盘所在的位置,设置有可能利用操作系统层面的工具拷贝ASM其中的数据出来。我将使用两个例子来说明如何查看au分布。 0. spfile 查看当前的spfile: sys@GT11G show parameter spfile; NAME TYPE VALUE -----
我们将尝试找出文件的AU分布,然后根据AU分布定位磁盘所在的位置,设置有可能利用操作系统层面的工具拷贝ASM其中的数据出来。我将使用两个例子来说明如何查看au分布。
0. spfile
查看当前的spfile:
sys@GT11G> show parameter spfile;
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
spfile string +DATA01/gt11g/spfilegt11g.ora
查找对应的DISKGROUP信息:
+ASM> select name,group_number,file_number from v$asm_alias where lower(name)='spfilegt11g.ora';
NAME GROUP_NUMBER FILE_NUMBER
-------------------- ------------ -----------
spfileGT11G.ora 1 265
+ASM> select name,group_number from v$asm_diskgroup;
NAME GROUP_NUMBER
-------- ------------
DATA01 1
FRA 2
SYSDG 3
通过视图查看对应的AU分布:
+ASM> select group_kffxp,number_kffxp,pxn_kffxp,xnum_kffxp,disk_kffxp from x$kffxp where group_kffxp=1 and number_kffxp=265;
GROUP_KFFXP NUMBER_KFFXP PXN_KFFXP XNUM_KFFXP DISK_KFFXP
----------- ------------ ---------- ---------- ----------
1 265 0 0 1
上述查询显示spfile文件在磁盘组1的0号磁盘上只占用了1个AU,那么我们可以直接通过kfed工具来查看下磁盘上的分配属性。
首先我们要找出对应的磁盘信息,注意磁盘序号是从0开始的:
+ASM> select group_number,disk_number,path from v$asm_disk where group_number=1 and disk_number=0;
GROUP_NUMBER DISK_NUMBER PATH
------------ ----------- --------------------
1 0 /dev/asm11g-f
文件的FILE_NUMBER=256,我们应该从au2这里面查找,也即asm元数据之后的第1个文件,而blkn0是保留位置,因此我们从blkn1开始查找:
[grid@gtser2 ~]$ kfed read /dev/asm11g-f aun=2 blkn=1 | more
kfbh.endian: 1 ; 0x000: 0x01
kfbh.hard: 130 ; 0x001: 0x82
kfbh.type: 4 ; 0x002: KFBTYP_FILEDIR
kfbh.datfmt: 1 ; 0x003: 0x01
kfbh.block.blk: 1 ; 0x004: blk=1
kfbh.block.obj: 1 ; 0x008: file=1
kfbh.check: 4093010779 ; 0x00c: 0xf3f6635b
kfbh.fcn.base: 443 ; 0x010: 0x000001bb
kfbh.fcn.wrap: 0 ; 0x014: 0x00000000
kfbh.spare1: 0 ; 0x018: 0x00000000
kfbh.spare2: 0 ; 0x01c: 0x00000000
kfffdb.node.incarn: 1 ; 0x000: A=1 NUMM=0x0
kfffdb.node.frlist.number: 4294967295 ; 0x004: 0xffffffff
kfffdb.node.frlist.incarn: 0 ; 0x008: A=0 NUMM=0x0
kfffdb.hibytes: 0 ; 0x00c: 0x00000000
kfffdb.lobytes: 2097152 ; 0x010: 0x00200000
kfffdb.xtntcnt: 2 ; 0x014: 0x00000002
kfffdb.xtnteof: 2 ; 0x018: 0x00000002
kfffdb.blkSize: 4096 ; 0x01c: 0x00001000
kfffdb.flags: 1 ; 0x020: O=1 S=0 S=0 D=0 C=0 I=0 R=0 A=0
kfffdb.fileType: 15 ; 0x021: 0x0f
kfffdb.dXrs: 17 ; 0x022: SCHE=0x1 NUMB=0x1
kfffdb.iXrs: 17 ; 0x023: SCHE=0x1 NUMB=0x1
kfffdb.dXsiz[0]: 4294967295 ; 0x024: 0xffffffff
kfffdb.dXsiz[1]: 0 ; 0x028: 0x00000000
kfffdb.dXsiz[2]: 0 ; 0x02c: 0x00000000
kfffdb.iXsiz[0]: 4294967295 ; 0x030: 0xffffffff
kfffdb.iXsiz[1]: 0 ; 0x034: 0x00000000
kfffdb.iXsiz[2]: 0 ; 0x038: 0x00000000
kfffdb.xtntblk: 2 ; 0x03c: 0x0002
kfffdb.break: 60 ; 0x03e: 0x003c
kfffdb.priZn: 0 ; 0x040: KFDZN_COLD
kfffdb.secZn: 0 ; 0x041: KFDZN_COLD
kfffdb.ub2spare: 0 ; 0x042: 0x0000
kfffdb.alias[0]: 4294967295 ; 0x044: 0xffffffff
kfffdb.alias[1]: 4294967295 ; 0x048: 0xffffffff
kfffdb.strpwdth: 0 ; 0x04c: 0x00
kfffdb.strpsz: 0 ; 0x04d: 0x00
kfffdb.usmsz: 0 ; 0x04e: 0x0000
kfffdb.crets.hi: 32984682 ; 0x050: HOUR=0xa DAYS=0x13 MNTH=0x3 YEAR=0x7dd
kfffdb.crets.lo: 3985358848 ; 0x054: USEC=0x0 MSEC=0x2f0 SECS=0x18 MINS=0x3b
kfffdb.modts.hi: 32984682 ; 0x058: HOUR=0xa DAYS=0x13 MNTH=0x3 YEAR=0x7dd
kfffdb.modts.lo: 3985358848 ; 0x05c: USEC=0x0 MSEC=0x2f0 SECS=0x18 MINS=0x3b
kfffdb.dasz[0]: 0 ; 0x060: 0x00
kfffdb.dasz[1]: 0 ; 0x061: 0x00
kfffdb.dasz[2]: 0 ; 0x062: 0x00
kfffdb.dasz[3]: 0 ; 0x063: 0x00
kfffdb.permissn: 0 ; 0x064: 0x00
kfffdb.ub1spar1: 0 ; 0x065: 0x00
kfffdb.ub2spar2: 0 ; 0x066: 0x0000
kfffdb.user.entnum: 0 ; 0x068: 0x0000
kfffdb.user.entinc: 0 ; 0x06a: 0x0000
kfffdb.group.entnum: 0 ; 0x06c: 0x0000
kfffdb.group.entinc: 0 ; 0x06e: 0x0000
kfffdb.spare[0]: 0 ; 0x070: 0x00000000
kfffdb.spare[1]: 0 ; 0x074: 0x00000000
kfffdb.spare[2]: 0 ; 0x078: 0x00000000
kfffdb.spare[3]: 0 ; 0x07c: 0x00000000
kfffdb.spare[4]: 0 ; 0x080: 0x00000000
kfffdb.spare[5]: 0 ; 0x084: 0x00000000
kfffdb.spare[6]: 0 ; 0x088: 0x00000000
kfffdb.spare[7]: 0 ; 0x08c: 0x00000000
kfffdb.spare[8]: 0 ; 0x090: 0x00000000
kfffdb.spare[9]: 0 ; 0x094: 0x00000000
kfffdb.spare[10]: 0 ; 0x098: 0x00000000
kfffdb.spare[11]: 0 ; 0x09c: 0x00000000
kfffdb.usm: ; 0x0a0: length=0
kfffde[0].xptr.au: 2 ; 0x4a0: 0x00000002
kfffde[0].xptr.disk: 0 ; 0x4a4: 0x0000
kfffde[0].xptr.flags: 0 ; 0x4a6: L=0 E=0 D=0 S=0
kfffde[0].xptr.chk: 40 ; 0x4a7: 0x28
kfffde[1].xptr.au: 31 ; 0x4a8: 0x0000001f
kfffde[1].xptr.disk: 1 ; 0x4ac: 0x0001
kfffde[1].xptr.flags: 0 ; 0x4ae: L=0 E=0 D=0 S=0
kfffde[1].xptr.chk: 52 ; 0x4af: 0x34
kfffde[2].xptr.au: 4294967295 ; 0x4b0: 0xffffffff
kfffde[2].xptr.disk: 65535 ; 0x4b4: 0xffff
kfffde[2].xptr.flags: 0 ; 0x4b6: L=0 E=0 D=0 S=0
kfffde[2].xptr.chk: 42 ; 0x4b7: 0x2a
注意上面的信息:
kfffde[1].xptr.au: 31 ; 0x4a8: 0x0000001f
kfffde[0].xptr.disk: 0 ; 0x4a4: 0x0000
这说明从256文件开始相关的au分布信息是放在这里的,我们继续查看这个au的信息:
+ASM> select group_number,disk_number,path from v$asm_disk where group_number=1 and disk_number=1;
GROUP_NUMBER DISK_NUMBER PATH
------------ ----------- --------------------
1 1 /dev/asm11g-g
而265号文件是存放在blkn=265-255=10,也即第10块中(blkn=9):
[grid@gtser2 ~]$ kfed read /dev/asm11g-g aun=31 blkn=9 | more
kfbh.endian: 1 ; 0x000: 0x01
kfbh.hard: 130 ; 0x001: 0x82
kfbh.type: 4 ; 0x002: KFBTYP_FILEDIR
kfbh.datfmt: 1 ; 0x003: 0x01
kfbh.block.blk: 265 ; 0x004: blk=265
kfbh.block.obj: 1 ; 0x008: file=1
kfbh.check: 3335649844 ; 0x00c: 0xc6d1fa34
kfbh.fcn.base: 3319 ; 0x010: 0x00000cf7
kfbh.fcn.wrap: 0 ; 0x014: 0x00000000
kfbh.spare1: 0 ; 0x018: 0x00000000
kfbh.spare2: 0 ; 0x01c: 0x00000000
kfffdb.node.incarn: 810479951 ; 0x000: A=1 NUMM=0x182778a7
kfffdb.node.frlist.number: 4294967295 ; 0x004: 0xffffffff
kfffdb.node.frlist.incarn: 0 ; 0x008: A=0 NUMM=0x0
kfffdb.hibytes: 0 ; 0x00c: 0x00000000
kfffdb.lobytes: 3584 ; 0x010: 0x00000e00
kfffdb.xtntcnt: 1 ; 0x014: 0x00000001
kfffdb.xtnteof: 1 ; 0x018: 0x00000001
kfffdb.blkSize: 512 ; 0x01c: 0x00000200
kfffdb.flags: 17 ; 0x020: O=1 S=0 S=0 D=0 C=1 I=0 R=0 A=0
kfffdb.fileType: 13 ; 0x021: 0x0d
kfffdb.dXrs: 17 ; 0x022: SCHE=0x1 NUMB=0x1
kfffdb.iXrs: 17 ; 0x023: SCHE=0x1 NUMB=0x1
kfffdb.dXsiz[0]: 4294967295 ; 0x024: 0xffffffff
kfffdb.dXsiz[1]: 0 ; 0x028: 0x00000000
kfffdb.dXsiz[2]: 0 ; 0x02c: 0x00000000
kfffdb.iXsiz[0]: 4294967295 ; 0x030: 0xffffffff
kfffdb.iXsiz[1]: 0 ; 0x034: 0x00000000
kfffdb.iXsiz[2]: 0 ; 0x038: 0x00000000
kfffdb.xtntblk: 1 ; 0x03c: 0x0001
kfffdb.break: 60 ; 0x03e: 0x003c
kfffdb.priZn: 0 ; 0x040: KFDZN_COLD
kfffdb.secZn: 0 ; 0x041: KFDZN_COLD
kfffdb.ub2spare: 0 ; 0x042: 0x0000
kfffdb.alias[0]: 318 ; 0x044: 0x0000013e
kfffdb.alias[1]: 58 ; 0x048: 0x0000003a
kfffdb.strpwdth: 1 ; 0x04c: 0x01
kfffdb.strpsz: 20 ; 0x04d: 0x14
kfffdb.usmsz: 0 ; 0x04e: 0x0000
kfffdb.crets.hi: 32984685 ; 0x050: HOUR=0xd DAYS=0x13 MNTH=0x3 YEAR=0x7dd
kfffdb.crets.lo: 1287023616 ; 0x054: USEC=0x0 MSEC=0x19b SECS=0xb MINS=0x13
kfffdb.modts.hi: 32984747 ; 0x058: HOUR=0xb DAYS=0x15 MNTH=0x3 YEAR=0x7dd
kfffdb.modts.lo: 0 ; 0x05c: USEC=0x0 MSEC=0x0 SECS=0x0 MINS=0x0
kfffdb.dasz[0]: 0 ; 0x060: 0x00
kfffdb.dasz[1]: 0 ; 0x061: 0x00
kfffdb.dasz[2]: 0 ; 0x062: 0x00
kfffdb.dasz[3]: 0 ; 0x063: 0x00
kfffdb.permissn: 0 ; 0x064: 0x00
kfffdb.ub1spar1: 0 ; 0x065: 0x00
kfffdb.ub2spar2: 0 ; 0x066: 0x0000
kfffdb.user.entnum: 0 ; 0x068: 0x0000
kfffdb.user.entinc: 0 ; 0x06a: 0x0000
kfffdb.group.entnum: 0 ; 0x06c: 0x0000
kfffdb.group.entinc: 0 ; 0x06e: 0x0000
kfffdb.spare[0]: 0 ; 0x070: 0x00000000
kfffdb.spare[1]: 0 ; 0x074: 0x00000000
kfffdb.spare[2]: 0 ; 0x078: 0x00000000
kfffdb.spare[3]: 0 ; 0x07c: 0x00000000
kfffdb.spare[4]: 0 ; 0x080: 0x00000000
kfffdb.spare[5]: 0 ; 0x084: 0x00000000
kfffdb.spare[6]: 0 ; 0x088: 0x00000000
kfffdb.spare[7]: 0 ; 0x08c: 0x00000000
kfffdb.spare[8]: 0 ; 0x090: 0x00000000
kfffdb.spare[9]: 0 ; 0x094: 0x00000000
kfffdb.spare[10]: 0 ; 0x098: 0x00000000
kfffdb.spare[11]: 0 ; 0x09c: 0x00000000
kfffdb.usm: ; 0x0a0: length=0
kfffde[0].xptr.au: 936 ; 0x4a0: 0x000003a8
kfffde[0].xptr.disk: 1 ; 0x4a4: 0x0001
kfffde[0].xptr.flags: 0 ; 0x4a6: L=0 E=0 D=0 S=0
kfffde[0].xptr.chk: 128 ; 0x4a7: 0x80
kfffde[1].xptr.au: 4294967295 ; 0x4a8: 0xffffffff
kfffde[1].xptr.disk: 65535 ; 0x4ac: 0xffff
kfffde[1].xptr.flags: 0 ; 0x4ae: L=0 E=0 D=0 S=0
kfffde[1].xptr.chk: 42 ; 0x4af: 0x2a
我们可以看到只有:
kfffde[0].xptr.au: 936 ; 0x4a0: 0x000003a8
而下一个:
kfffde[1].xptr.au: 4294967295 ; 0x4a8: 0xffffffff
是还没分配数据的,这也印证了我们的配置,,external的dg,没有冗余,因此每个au只有primary extents,即1个au,接下来我们通过os的dd命令将该文件copy出来,我们可以直接将spfile dd到文本文件:
+ASM> select group_kfdat,number_kfdat,aunum_kfdat from x$kfdat where fnum_kfdat=265;
GROUP_KFDAT NUMBER_KFDAT AUNUM_KFDAT
----------- ------------ -----------
1 1 936
从上面信息我们得到该文件业绩spfile的在磁盘的物理位置:
[grid@gtser2 ~]$ dd if=/dev/asm11g-g skip=936 of=/tmp/dbspfile bs=1024k count=1
1+0 records in
1+0 records out
1048576 bytes (1.0 MB) copied, 0.00721405 seconds, 145 MB/s
[grid@gtser2 ~]$ cat /tmp/dbspfile
C"(%3tQ0CC"yKGT11G.__db_cache_size=301989888
GT11G.__java_pool_size=4194304
GT11G.__large_pool_size=4194304
GT11G.__oracle_base='/u02/app/oracle'#ORACLE_BASE set from environment
GT11G.__pga_aggregate_target=159383552
GT11G.__sga_target=469762048
GT11G.__shared_io_pool_size=0
GT11G.__shared_pool_size=146800640
GT11G.__streams_pool_size=0
*.audit_file_dest='/u02/app/oracle/admin/GT11G/adump'
*.audit_trail='db'
*.compatible='11.2.0.0.0'
*.control_files='+DATA01/gt11g/controlfile/current.256.8104718CC"y/79','+FRA/gt11g/controlfile/current.256.810471883'
*.db_block_size=8192
*.db_create_file_dest='+DATA01'
*.db_domain=''
*.db_name='GT11G'
*.db_recovery_file_dest='+FRA'
*.db_recovery_file_dest_size=5218762752
*.diagnostic_dest='/u02/app/oracle'
*.dispatchers='(PROTOCOL=TCP) (SERVICE=GT11GXDB)'
*.log_archive_format='%t_%s_%r.dbf'
*.nls_language='SIMPLIFIED CHINESE'
*.nls_territory='CHINA'
*.open_cursors=300
*.pga_aggregate_target=156237824
*.processes=150
*.remote_login_passwordfile='ECC"YcXCLUSIVE'
*.sga_target=469762048
*.undo_tablespace='UNDOTBS1'
CC"FeCC"EeCC"DeC[grid@gtser2 ~]$
0. 控制文件
sys@GT11G> show parameter control_files
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
control_files string +DATA01/gt11g/controlfile/curr
ent.256.810471879, +FRA/gt11g/
controlfile/current.256.810471
883
+ASM> select XNUM_KFFXP , PXN_KFFXP , LXN_KFFXP , DISK_KFFXP , AU_KFFXP,size_kffxp
2 from X$KFFXP
3 where GROUP_KFFXP=1 and NUMBER_KFFXP=256 and XNUM_KFFXP2147483648
4 order by 1,2;
XNUM_KFFXP PXN_KFFXP LXN_KFFXP DISK_KFFXP AU_KFFXP SIZE_KFFXP
---------- ---------- ---------- ---------- ---------- ----------
0 0 0 1 32 1
1 1 0 0 29 1
2 2 0 1 33 1
3 3 0 0 30 1
4 4 0 1 34 1
5 5 0 0 31 1
6 6 0 1 35 1
7 7 0 0 32 1
8 8 0 1 36 1
9 9 0 0 33 1
10 10 0 1 37 1
11 11 0 0 34 1
12 12 0 1 38 1
13 13 0 0 35 1
14 14 0 1 39 1
15 15 0 0 36 1
16 rows selected.
这个控制文件使用了16个au,我们看看实际的磁盘分布情况怎么样:
[grid@gtser2 ~]$ kfed read /dev/asm11g-g aun=31 blkn=0 | more
kfbh.endian: 1 ; 0x000: 0x01
kfbh.hard: 130 ; 0x001: 0x82
kfbh.type: 4 ; 0x002: KFBTYP_FILEDIR
kfbh.datfmt: 1 ; 0x003: 0x01
kfbh.block.blk: 256 ; 0x004: blk=256
kfbh.block.obj: 1 ; 0x008: file=1
kfbh.check: 179031737 ; 0x00c: 0x0aabceb9
kfbh.fcn.base: 3301 ; 0x010: 0x00000ce5
kfbh.fcn.wrap: 0 ; 0x014: 0x00000000
kfbh.spare1: 0 ; 0x018: 0x00000000
kfbh.spare2: 0 ; 0x01c: 0x00000000
kfffdb.node.incarn: 810471879 ; 0x000: A=1 NUMM=0x182768e3
kfffdb.node.frlist.number: 4294967295 ; 0x004: 0xffffffff
kfffdb.node.frlist.incarn: 0 ; 0x008: A=0 NUMM=0x0
kfffdb.hibytes: 0 ; 0x00c: 0x00000000
kfffdb.lobytes: 9748480 ; 0x010: 0x0094c000
kfffdb.xtntcnt: 16 ; 0x014: 0x00000010
kfffdb.xtnteof: 16 ; 0x018: 0x00000010
kfffdb.blkSize: 16384 ; 0x01c: 0x00004000
kfffdb.flags: 19 ; 0x020: O=1 S=1 S=0 D=0 C=1 I=0 R=0 A=0
kfffdb.fileType: 1 ; 0x021: 0x01
kfffdb.dXrs: 17 ; 0x022: SCHE=0x1 NUMB=0x1
kfffdb.iXrs: 17 ; 0x023: SCHE=0x1 NUMB=0x1
kfffdb.dXsiz[0]: 4294967295 ; 0x024: 0xffffffff
kfffdb.dXsiz[1]: 0 ; 0x028: 0x00000000
kfffdb.dXsiz[2]: 0 ; 0x02c: 0x00000000
kfffdb.iXsiz[0]: 4294967295 ; 0x030: 0xffffffff
kfffdb.iXsiz[1]: 0 ; 0x034: 0x00000000
kfffdb.iXsiz[2]: 0 ; 0x038: 0x00000000
kfffdb.xtntblk: 16 ; 0x03c: 0x0010
kfffdb.break: 60 ; 0x03e: 0x003c
kfffdb.priZn: 0 ; 0x040: KFDZN_COLD
kfffdb.secZn: 0 ; 0x041: KFDZN_COLD
kfffdb.ub2spare: 0 ; 0x042: 0x0000
kfffdb.alias[0]: 106 ; 0x044: 0x0000006a
kfffdb.alias[1]: 4294967295 ; 0x048: 0xffffffff
kfffdb.strpwdth: 8 ; 0x04c: 0x08
kfffdb.strpsz: 17 ; 0x04d: 0x11
kfffdb.usmsz: 0 ; 0x04e: 0x0000
kfffdb.crets.hi: 32984683 ; 0x050: HOUR=0xb DAYS=0x13 MNTH=0x3 YEAR=0x7dd
kfffdb.crets.lo: 307757056 ; 0x054: USEC=0x0 MSEC=0x200 SECS=0x25 MINS=0x4
kfffdb.modts.hi: 32984745 ; 0x058: HOUR=0x9 DAYS=0x15 MNTH=0x3 YEAR=0x7dd
kfffdb.modts.lo: 0 ; 0x05c: USEC=0x0 MSEC=0x0 SECS=0x0 MINS=0x0
kfffdb.dasz[0]: 0 ; 0x060: 0x00
kfffdb.dasz[1]: 0 ; 0x061: 0x00
kfffdb.dasz[2]: 0 ; 0x062: 0x00
kfffdb.dasz[3]: 0 ; 0x063: 0x00
kfffdb.permissn: 0 ; 0x064: 0x00
kfffdb.ub1spar1: 0 ; 0x065: 0x00
kfffdb.ub2spar2: 0 ; 0x066: 0x0000
kfffdb.user.entnum: 0 ; 0x068: 0x0000
kfffdb.user.entinc: 0 ; 0x06a: 0x0000
kfffdb.group.entnum: 0 ; 0x06c: 0x0000
kfffdb.group.entinc: 0 ; 0x06e: 0x0000
kfffdb.spare[0]: 0 ; 0x070: 0x00000000
kfffdb.spare[1]: 0 ; 0x074: 0x00000000
kfffdb.spare[2]: 0 ; 0x078: 0x00000000
kfffdb.spare[3]: 0 ; 0x07c: 0x00000000
kfffdb.spare[4]: 0 ; 0x080: 0x00000000
kfffdb.spare[5]: 0 ; 0x084: 0x00000000
kfffdb.spare[6]: 0 ; 0x088: 0x00000000
kfffdb.spare[7]: 0 ; 0x08c: 0x00000000
kfffdb.spare[8]: 0 ; 0x090: 0x00000000
kfffdb.spare[9]: 0 ; 0x094: 0x00000000
kfffdb.spare[10]: 0 ; 0x098: 0x00000000
kfffdb.spare[11]: 0 ; 0x09c: 0x00000000
kfffdb.usm: ; 0x0a0: length=0
kfffde[0].xptr.au: 32 ; 0x4a0: 0x00000020
kfffde[0].xptr.disk: 1 ; 0x4a4: 0x0001
kfffde[0].xptr.flags: 0 ; 0x4a6: L=0 E=0 D=0 S=0
kfffde[0].xptr.chk: 11 ; 0x4a7: 0x0b
kfffde[1].xptr.au: 29 ; 0x4a8: 0x0000001d
kfffde[1].xptr.disk: 0 ; 0x4ac: 0x0000
kfffde[1].xptr.flags: 0 ; 0x4ae: L=0 E=0 D=0 S=0
kfffde[1].xptr.chk: 55 ; 0x4af: 0x37
kfffde[2].xptr.au: 33 ; 0x4b0: 0x00000021
kfffde[2].xptr.disk: 1 ; 0x4b4: 0x0001
kfffde[2].xptr.flags: 0 ; 0x4b6: L=0 E=0 D=0 S=0
kfffde[2].xptr.chk: 10 ; 0x4b7: 0x0a
kfffde[3].xptr.au: 30 ; 0x4b8: 0x0000001e
kfffde[3].xptr.disk: 0 ; 0x4bc: 0x0000
kfffde[3].xptr.flags: 0 ; 0x4be: L=0 E=0 D=0 S=0
kfffde[3].xptr.chk: 52 ; 0x4bf: 0x34
kfffde[4].xptr.au: 34 ; 0x4c0: 0x00000022
kfffde[4].xptr.disk: 1 ; 0x4c4: 0x0001
kfffde[4].xptr.flags: 0 ; 0x4c6: L=0 E=0 D=0 S=0
kfffde[4].xptr.chk: 9 ; 0x4c7: 0x09
kfffde[5].xptr.au: 31 ; 0x4c8: 0x0000001f
kfffde[5].xptr.disk: 0 ; 0x4cc: 0x0000
kfffde[5].xptr.flags: 0 ; 0x4ce: L=0 E=0 D=0 S=0
kfffde[5].xptr.chk: 53 ; 0x4cf: 0x35
kfffde[6].xptr.au: 35 ; 0x4d0: 0x00000023
kfffde[6].xptr.disk: 1 ; 0x4d4: 0x0001
kfffde[6].xptr.flags: 0 ; 0x4d6: L=0 E=0 D=0 S=0
kfffde[6].xptr.chk: 8 ; 0x4d7: 0x08
kfffde[7].xptr.au: 32 ; 0x4d8: 0x00000020
kfffde[7].xptr.disk: 0 ; 0x4dc: 0x0000
kfffde[7].xptr.flags: 0 ; 0x4de: L=0 E=0 D=0 S=0
kfffde[7].xptr.chk: 10 ; 0x4df: 0x0a
kfffde[8].xptr.au: 36 ; 0x4e0: 0x00000024
kfffde[8].xptr.disk: 1 ; 0x4e4: 0x0001
kfffde[8].xptr.flags: 0 ; 0x4e6: L=0 E=0 D=0 S=0
kfffde[8].xptr.chk: 15 ; 0x4e7: 0x0f
kfffde[9].xptr.au: 33 ; 0x4e8: 0x00000021
kfffde[9].xptr.disk: 0 ; 0x4ec: 0x0000
kfffde[9].xptr.flags: 0 ; 0x4ee: L=0 E=0 D=0 S=0
kfffde[9].xptr.chk: 11 ; 0x4ef: 0x0b
kfffde[10].xptr.au: 37 ; 0x4f0: 0x00000025
kfffde[10].xptr.disk: 1 ; 0x4f4: 0x0001
kfffde[10].xptr.flags: 0 ; 0x4f6: L=0 E=0 D=0 S=0
kfffde[10].xptr.chk: 14 ; 0x4f7: 0x0e
kfffde[11].xptr.au: 34 ; 0x4f8: 0x00000022
kfffde[11].xptr.disk: 0 ; 0x4fc: 0x0000
kfffde[11].xptr.flags: 0 ; 0x4fe: L=0 E=0 D=0 S=0
kfffde[11].xptr.chk: 8 ; 0x4ff: 0x08
kfffde[12].xptr.au: 38 ; 0x500: 0x00000026
kfffde[12].xptr.disk: 1 ; 0x504: 0x0001
kfffde[12].xptr.flags: 0 ; 0x506: L=0 E=0 D=0 S=0
kfffde[12].xptr.chk: 13 ; 0x507: 0x0d
kfffde[13].xptr.au: 35 ; 0x508: 0x00000023
kfffde[13].xptr.disk: 0 ; 0x50c: 0x0000
kfffde[13].xptr.flags: 0 ; 0x50e: L=0 E=0 D=0 S=0
kfffde[13].xptr.chk: 9 ; 0x50f: 0x09
kfffde[14].xptr.au: 39 ; 0x510: 0x00000027
kfffde[14].xptr.disk: 1 ; 0x514: 0x0001
kfffde[14].xptr.flags: 0 ; 0x516: L=0 E=0 D=0 S=0
kfffde[14].xptr.chk: 12 ; 0x517: 0x0c
kfffde[15].xptr.au: 36 ; 0x518: 0x00000024
kfffde[15].xptr.disk: 0 ; 0x51c: 0x0000
kfffde[15].xptr.flags: 0 ; 0x51e: L=0 E=0 D=0 S=0
kfffde[15].xptr.chk: 14 ; 0x51f: 0x0e
kfffde[16].xptr.au: 4294967295 ; 0x520: 0xffffffff
kfffde[16].xptr.disk: 65535 ; 0x524: 0xffff
kfffde[16].xptr.flags: 0 ; 0x526: L=0 E=0 D=0 S=0
kfffde[16].xptr.chk: 42 ; 0x527: 0x2a
kfffde[17].xptr.au: 4294967295 ; 0x528: 0xffffffff
kfffde[17].xptr.disk: 65535 ; 0x52c: 0xffff
kfffde[17].xptr.flags: 0 ; 0x52e: L=0 E=0 D=0 S=0
kfffde[17].xptr.chk: 42 ; 0x52f: 0x2a
kfffde[18].xptr.au: 4294967295 ; 0x530: 0xffffffff
这个结果符合我们的预期,占用了16个au也即16Mb:
sys@GT11G> select name,block_size/1024 from v$controlfile ;
NAME BLOCK_SIZE/1024
-------------------------------------------------- ---------------
+DATA01/gt11g/controlfile/current.256.810471879 16
+FRA/gt11g/controlfile/current.256.810471883 16
-EOF-

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