[20190423]oradebug peek测试脚本.txt

--//工作测试需要写一个oradebug peek测试脚本,不断看某个区域内存地址的值。

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

2.建立测试例子：

create table t as select rownum id,'test' name from dual ;

create unique index pk_t on t(id);

alter table t modify id  not null ;

--//分析表和索引略.

SCOTT@book> select rowid,t.* from t;

ROWID                      ID NAME

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

AAAknXAAEAAAAILAAA          1 test

SCOTT@book> @ rowid AAAknXAAEAAAAILAAA

    OBJECT       FILE      BLOCK        ROW ROWID_DBA            DBA                  TEXT

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

    149975          4        523          0  0x100020B           4,523                alter system dump datafile 4 block 523 ;

SCOTT@book> select header_file,header_block from dba_segments where owner=user and segment_name='PK_T';

HEADER_FILE HEADER_BLOCK

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

          4          554

--//从以上信息可以知道dba=4,523数据块,dba=4,522表T段头.dba=4,555(554+1)是索引的root块(因为索引很小也是叶子和分支块)

SYS@book> @ bh 4 522

HLADDR              DBARFIL     DBABLK      CLASS CLASS_TYPE         STATE             TCH CR_SCN_BAS CR_SCN_WRP CR_UBA_FIL CR_UBA_BLK CR_UBA_SEQ BA               OBJECT_NAME

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

0000000084DA2730          4        522          4 segment header     xcur                1          0          0          0          0          0 0000000071F46000 T

SYS@book> @ bh 4 523

HLADDR              DBARFIL     DBABLK      CLASS CLASS_TYPE         STATE             TCH CR_SCN_BAS CR_SCN_WRP CR_UBA_FIL CR_UBA_BLK CR_UBA_SEQ BA               OBJECT_NAME

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

0000000084C92150          4        523          1 data block         xcur                2          0          0          0          0          0 0000000072208000 T

SYS@book> @ bh 4 555

HLADDR              DBARFIL     DBABLK      CLASS CLASS_TYPE         STATE             TCH CR_SCN_BAS CR_SCN_WRP CR_UBA_FIL CR_UBA_BLK CR_UBA_SEQ BA               OBJECT_NAME

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

000000008577A438          4        555          1 data block         xcur                1          0          0          0          0          0 00000000721E2000 PK_T

--//获得这些块的cbc latch地址。

--//0000000084da2730,0000000084c92150,000000008577a438

3.编写脚本:

$ cat peek_laddr.sh

#! /bin/bash

# argument : laddr_list(delimiter using ,)  Monitor_count  peek_length sleep_duration

vdate=$(date '+%Y%m%d%H%M%S')

echo $vdate

laddr_list=$(echo $1| tr ',' '\n')

# p=$(echo "$laddr_list"|wc -l)

# echo $p

>| /tmp/pp_${vdate}.txt

for a in $laddr_list

do

        sqlplus -s -l / as sysdba <<EOF | timestamp.pl  >> /tmp/pp_${vdate}_${a}.txt &

oradebug setmypid

$(seq $2 | xargs -I{} echo  -e "oradebug peek 0x$a  $3\nhost sleep $4" )

quit

EOF

done

--//写的很丑陋,不过能用^_^.

$ cat z1.txt

set verify off

host sleep $(echo &&3/50 | bc -l )

variable vmethod varchar2(20);

exec :vmethod := '&&2';

insert into job_times values ( sys_context ('userenv', 'sid') ,dbms_utility.get_time ,:vmethod) ;

commit ;

declare

v_id number;

v_d date;

v_name varchar2(4) ;

begin

    for i in 1 .. &&1 loop

        --//select /*+ index(t) &&3 */ count (*) into v_id from t ;

        select /*+ full(t) &&3 */ count (*) into v_id from t ;

    end loop;

end ;

/

update job_times set time_ela = dbms_utility.get_time - time_ela where sid=sys_context ('userenv', 'sid') and method=:vmethod;

commit;

quit

4.测试脚本

-//编写脚本如下：

$ cat aaa.sh

#! /bin/bash

#vdate=$(date '+%Y%m%d%H%M%S')

#echo $vdate

laddr_list="$1"

echo $laddr_list

source peek_laddr.sh ${laddr_list} 200 8 0.1 &

seq 50 | xargs -I{} -P 50 sqlplus -s -l scott/book @z1.txt 1e5 id=index1 {} >/dev/null &

--//说明测试最好避开awr报表生成时间点.没有其它事务执行sql语句.

$ . aaa.sh 000000084da2730,0000000084c92150,000000008577a438

000000084da2730,0000000084c92150,000000008577a438

20190430104022

[1]-  Done                    source peek_laddr.sh ${laddr_list} 100 8 0.1

[2]+  Done                    seq 50 | xargs -I{} -P 50 sqlplus -s -l scott/book @z1.txt 1e5 id=full50 {} > /dev/null

--//等10秒看看.

SCOTT@book> Select method,count(*),round(avg(TIME_ELA),0),sum(TIME_ELA) from job_times group by method order by 3 ;

METHOD                 COUNT(*) ROUND(AVG(TIME_ELA),0) SUM(TIME_ELA)

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

id=full50                    50                    977         48864

$ echo 000000084da2730,0000000084c92150,000000008577a438 | tr ',' '\n' | xargs -I{} grep  -v '^.*: $' /tmp/pp_20190430104022_{}.txt |cut -c10- |sort| uniq -c

     71  [084C92150, 084C92158) = 00000000 00000000

     21  [084C92150, 084C92158) = 00000001 00000000

      7  [084C92150, 084C92158) = 00000002 00000000

      1  [084C92150, 084C92158) = 00000004 00000000

     60  [084DA2730, 084DA2738) = 00000000 00000000

     27  [084DA2730, 084DA2738) = 00000001 00000000

     12  [084DA2730, 084DA2738) = 00000002 00000000

      1  [084DA2730, 084DA2738) = 00000003 00000000

    100  [08577A438, 08577A440) = 00000000 00000000

      3  Statement processed.

--//没有访问索引root节点块.

--//你可以发现大部分都是00000000 00000000.

--//可以发现没有任何阻塞,shared latch,我在链接的测试总结如下:http://blog.itpub.net/267265/viewspace-2641414/

--//总结:

--//A. S mode 下: peek记录的前4位持有S mode的数量.后4位是0x0. (这里针对的64位的系统)

--//B. S mode 下,如果出现X mode,peek记录的前4位持有S mode的数量.后4位是0x40000000.

--//一旦X mode持有变成 前4位持有会话PID号,后4位0x20000000.

--//你可以发现全表扫描的情况下这些块都是S模式获取.

--//我加大数据量(2e5)以及监测时间(200次)

$ cat aaa.sh

#! /bin/bash

#vdate=$(date '+%Y%m%d%H%M%S')

#echo $vdate

laddr_list="$1"

echo $laddr_list

source peek_laddr.sh ${laddr_list} 200 8 0.1 &

seq 50 | xargs -I{} -P 50 sqlplus -s -l scott/book @z1.txt 2e5 id=full50 {} >/dev/null &

$ echo 000000084da2730,0000000084c92150,000000008577a438 | tr ',' '\n' | xargs -I{} grep  -v '^.*: $' /tmp/pp_20190430104409_{}.txt |cut -c10- |sort| uniq -c

    150  [084C92150, 084C92158) = 00000000 00000000

     23  [084C92150, 084C92158) = 00000001 00000000

     22  [084C92150, 084C92158) = 00000002 00000000

      5  [084C92150, 084C92158) = 00000003 00000000

    124  [084DA2730, 084DA2738) = 00000000 00000000

     35  [084DA2730, 084DA2738) = 00000001 00000000

     25  [084DA2730, 084DA2738) = 00000002 00000000

     11  [084DA2730, 084DA2738) = 00000003 00000000

      4  [084DA2730, 084DA2738) = 00000004 00000000

      1  [084DA2730, 084DA2738) = 00000005 00000000

    200  [08577A438, 08577A440) = 00000000 00000000

      3  Statement processed.

--//后4位全部是00000000.

5.如果改用索引呢?

--//修改z1.txt如下:

$ cat z1.txt

set verify off

host sleep $(echo &&3/50 | bc -l )

variable vmethod varchar2(20);

exec :vmethod := '&&2';

insert into job_times values ( sys_context ('userenv', 'sid') ,dbms_utility.get_time ,:vmethod) ;

commit ;

declare

v_id number;

v_d date;

v_name varchar2(4) ;

begin

    for i in 1 .. &&1 loop

        select /*+ index(t) &&3 */ count (*) into v_id from t ;

        --//select /*+ full(t) &&3 */ count (*) into v_id from t ;

    end loop;

end ;

/

update job_times set time_ela = dbms_utility.get_time - time_ela where sid=sys_context ('userenv', 'sid') and method=:vmethod;

commit;

quit

$ cat aaa.sh

#! /bin/bash

#vdate=$(date '+%Y%m%d%H%M%S')

#echo $vdate

laddr_list="$1"

echo $laddr_list

source peek_laddr.sh ${laddr_list} 240 8 0.1 &

seq 50 | xargs -I{} -P 50 sqlplus -s -l scott/book @z1.txt 1e5 id=index50 {} >/dev/null &

--//前面我的测试需要24秒之内完成.

$ . aaa.sh 000000084da2730,0000000084c92150,000000008577a438

000000084da2730,0000000084c92150,000000008577a438

$ 20190430104822

[1]-  Done                    source peek_laddr.sh ${laddr_list} 240 8 0.1

[2]+  Done                    seq 50 | xargs -I{} -P 50 sqlplus -s -l scott/book @z1.txt 1e5 id=index50 {} > /dev/null

SCOTT@book> Select method,count(*),round(avg(TIME_ELA),0),sum(TIME_ELA) from job_times group by method order by 3 ;

METHOD                 COUNT(*) ROUND(AVG(TIME_ELA),0) SUM(TIME_ELA)

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

id=index50                   50                   2268        113411

$ echo 000000084da2730,0000000084c92150,000000008577a438 | tr ',' '\n' | xargs -I{} grep  -v '^.*: $' /tmp/pp_20190430104822_{}.txt |cut -c10- |sort| uniq -c

    240  [084C92150, 084C92158) = 00000000 00000000

    240  [084DA2730, 084DA2738) = 00000000 00000000

--//注:没有访问数据块.dba=4,522 4,523.

     29  [08577A438, 08577A440) = 00000000 00000000

     18  [08577A438, 08577A440) = 00000000 20000000

     19  [08577A438, 08577A440) = 00000001 00000000

     12  [08577A438, 08577A440) = 00000001 20000000

      3  [08577A438, 08577A440) = 00000001 40000000

     17  [08577A438, 08577A440) = 00000002 00000000

      2  [08577A438, 08577A440) = 00000002 20000000

      1  [08577A438, 08577A440) = 00000002 40000000

     11  [08577A438, 08577A440) = 00000003 00000000

      1  [08577A438, 08577A440) = 00000003 40000000

      7  [08577A438, 08577A440) = 00000004 00000000

      1  [08577A438, 08577A440) = 00000005 00000000

      1  [08577A438, 08577A440) = 00000006 00000000

      1  [08577A438, 08577A440) = 00000007 00000000

      2  [08577A438, 08577A440) = 0000001B 20000000

      3  [08577A438, 08577A440) = 0000001D 20000000

      2  [08577A438, 08577A440) = 0000001E 20000000

      1  [08577A438, 08577A440) = 0000001F 00000000

      3  [08577A438, 08577A440) = 0000001F 20000000

      2  [08577A438, 08577A440) = 00000020 00000000

      3  [08577A438, 08577A440) = 00000020 20000000

      2  [08577A438, 08577A440) = 00000021 00000000

      1  [08577A438, 08577A440) = 00000021 20000000

      3  [08577A438, 08577A440) = 00000022 20000000

      1  [08577A438, 08577A440) = 00000023 20000000

      1  [08577A438, 08577A440) = 00000024 00000000

      1  [08577A438, 08577A440) = 00000024 20000000

      1  [08577A438, 08577A440) = 00000025 20000000

      1  [08577A438, 08577A440) = 00000026 20000000

      1  [08577A438, 08577A440) = 00000027 00000000

      3  [08577A438, 08577A440) = 00000027 20000000

      1  [08577A438, 08577A440) = 00000028 00000000

      2  [08577A438, 08577A440) = 00000028 20000000

      2  [08577A438, 08577A440) = 00000029 20000000

      2  [08577A438, 08577A440) = 0000002A 00000000

      2  [08577A438, 08577A440) = 0000002A 20000000

      2  [08577A438, 08577A440) = 0000002B 20000000

      3  [08577A438, 08577A440) = 0000002C 20000000

      1  [08577A438, 08577A440) = 0000002E 20000000

      3  [08577A438, 08577A440) = 0000002F 00000000

      2  [08577A438, 08577A440) = 0000002F 20000000

      2  [08577A438, 08577A440) = 00000030 20000000

      2  [08577A438, 08577A440) = 00000031 20000000

      1  [08577A438, 08577A440) = 00000032 20000000

      2  [08577A438, 08577A440) = 00000033 00000000

      1  [08577A438, 08577A440) = 00000034 00000000

      6  [08577A438, 08577A440) = 00000034 20000000

      3  [08577A438, 08577A440) = 00000035 20000000

      1  [08577A438, 08577A440) = 00000036 00000000

      1  [08577A438, 08577A440) = 00000037 00000000

      1  [08577A438, 08577A440) = 00000038 00000000

      3  [08577A438, 08577A440) = 00000038 20000000

      1  [08577A438, 08577A440) = 00000039 20000000

      3  [08577A438, 08577A440) = 0000003A 20000000

      2  [08577A438, 08577A440) = 0000003B 20000000

      1  [08577A438, 08577A440) = 0000003C 00000000

      2  [08577A438, 08577A440) = 0000003C 20000000

      1  [08577A438, 08577A440) = 0000003D 00000000

      1  [08577A438, 08577A440) = 0000003D 20000000

      2  [08577A438, 08577A440) = 0000003E 20000000

      2  [08577A438, 08577A440) = 0000003F 00000000

      1  [08577A438, 08577A440) = 0000003F 20000000

      1  [08577A438, 08577A440) = 00000040 20000000

      2  [08577A438, 08577A440) = 00000041 20000000

      2  [08577A438, 08577A440) = 00000042 20000000

      1  [08577A438, 08577A440) = 00000044 20000000

      2  [08577A438, 08577A440) = 00000045 20000000

      1  [08577A438, 08577A440) = 00000046 00000000

      3  [08577A438, 08577A440) = 00000046 20000000

      3  [08577A438, 08577A440) = 00000047 20000000

      2  [08577A438, 08577A440) = 00000048 20000000

      1  [08577A438, 08577A440) = 00000049 20000000

      1  [08577A438, 08577A440) = 0000004A 20000000

      1  [08577A438, 08577A440) = 0000004B 00000000

      2  [08577A438, 08577A440) = 0000004B 20000000

      5  [08577A438, 08577A440) = 0000004C 20000000

      3  Statement processed.

$ echo 000000084da2730,0000000084c92150,000000008577a438 | tr ',' '\n' | xargs -I{} grep  -v '^.*: $' /tmp/pp_20190430104822_{}.txt |cut -c10- |sort| uniq -c | grep 08577A438| sort -nr | head

     29  [08577A438, 08577A440) = 00000000 00000000

     19  [08577A438, 08577A440) = 00000001 00000000

     18  [08577A438, 08577A440) = 00000000 20000000

     17  [08577A438, 08577A440) = 00000002 00000000

     12  [08577A438, 08577A440) = 00000001 20000000

     11  [08577A438, 08577A440) = 00000003 00000000

      7  [08577A438, 08577A440) = 00000004 00000000

      6  [08577A438, 08577A440) = 00000034 20000000

      5  [08577A438, 08577A440) = 0000004C 20000000

      3  [08577A438, 08577A440) = 00000047 20000000

$ grep " 40000000$" /tmp/pp_20190430104822_000000008577a438.txt

10:48:23: [08577A438, 08577A440) = 00000001 40000000

10:48:35: [08577A438, 08577A440) = 00000001 40000000

10:48:37: [08577A438, 08577A440) = 00000003 40000000

10:48:44: [08577A438, 08577A440) = 00000001 40000000

10:48:45: [08577A438, 08577A440) = 00000002 40000000

--//我估计全部扫描全部使用是S mode获取cbc latch.而 INDEX FULL SCAN我估计有部分操作采用X mode获取cbc latch.

--//这也许就是为什么11g全表扫描快于INDEX FULL SCAN的原因吗?

--//实际上这个给oracle一些优化提供一些信息,比如一个表dept,经常查询deptno,DNAME两个字段,如果通过建立符合索引减少逻辑读.

--//如果程序出现大量频繁访问,反而全表扫描会更快.因为可能遇到cbc latch更少.

--//优化一定要考虑这些细节.有许多还是不是很清楚,先放一下...实际上仅仅11.2.0.4才会出现这样的情况.全表扫描快于INDEX FULL SCAN.