[20190423]oradebug peek测试脚本.txt

[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.