[20190416]完善shared latch测试脚本2.txt

--//昨天测试shared latch,链接:http://blog.itpub.net/267265/viewspace-2641414/,感觉有点开窍了.^_^.

http://andreynikolaev.wordpress.com/2010/11/17/shared-latch-behaves-like-enqueue/

For the shared latches Oracle 10g uses kslgetsl(laddr, wait, why, where, mode) function. Oracle 11g has kslgetsl_w()
function with the same interface, but internally uses ksl_get_shared_latch(). Like in my previous post, I guess the
meaning of kslgetsl() arguments as:

--//对于共享锁存，Oracle 10g使用kslgetsl(laddr，wait，why，where，mode)函数。Oracle 11g具有相同接口的kslgetsl_w()函数，但
--//在内部使用ksl_get_share_latch()。与上一篇文章一样，我认为kslgetsl()参数的含义是：
--//注:我以前一直以为还是kslgetsl,原来11g已经改为kslgetsl_w,不过内部使用还是ksl_get_shared_latch().

    laddress -- address of latch in SGA
    wait     -- flag. If not 0, then willing-to-wait latch get
    why      -- context why the latch is acquired at this where.
    where    -- location from where the latch is acquired (x$ksllw.indx)

And the last one is:

    mode – Exclusive or shared mode

the mode argument took only two values:
     8 -- "SHARED"
    16 -- "EXCLUSIVE"

--//我当时的测试针对'gcs partitioned table hash'  latch,完善修改测试脚本,增加一些通用性.

1.环境:
SYS@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

$ cat peek.sh
#! /bib/bash
# 参数如下:latch_name Monitoring_duration
sqlplus -s -l / as sysdba <<EOF
col laddr new_value laddr
SELECT sysdate,addr laddr FROM v\$latch_parent WHERE NAME='$1';
oradebug setmypid
$(seq $2|xargs -I{} echo -e 'oradebug peek 0x&laddr 8\nhost sleep 1' )
EOF

$ cat shared_latch.txt
/* 参数如下: @ latch.txt latch_name willing why where mode sleep_num */
connect / as sysdba
col laddr new_value laddr
col vmode  new_value vmode
select decode(lower('&&5'),'s',8,'x',16,'8',8,'16',16) vmode from dual ;
SELECT addr laddr FROM v$latch_parent WHERE NAME='&&1';
oradebug setmypid
oradebug call kslgetsl_w 0x&laddr &&2 &&3 &&4  &vmode
host sleep &&6
oradebug call kslfre 0x&laddr
exit

$ cat latch_free.sql
/*
     This file is part of demos for "Contemporary Latch Internals" seminar v.18.09.2010
     Andrey S. Nikolaev (Andrey.Nikolaev@rdtex.ru)
     http://AndreyNikolaev.wordpress.com

     This query shows trees of processes currently holding and waiting for latches
     Tree output enumerates these processes and latches as following:
Process <PID1>
 <latch1 holding by PID1>
    <processes waiting for latch1>
       ...
 <latch2 holding by PID1&