DBMS_HPROF包是oracle 11g出现的工具,是DBMS_PROFILER和DBMS_TRACE的综合.这里简单演示如何使用DBMS_HPROF包来分析存储过程性能信
DBMS_HPROF包是Oracle 11g出现的工具,是DBMS_PROFILER和DBMS_TRACE的综合.
这里简单演示如何使用DBMS_HPROF包来分析存储过程性能信息.
首先我们需要执行一个脚本来生成保存相关信息的表.
使用SYS用户执行$ORACLE_HOME/rdbms/admin/dbmshptab.sql
然后创建directory,
CREATE DIRECTORY LOG_FILE_DIR AS '/home/oracle';
先用SCOTT用户创建一个用于测试的存储过程insert_emp.
23:58:57 @ORCL> conn scott/tiger@orcl
Connected.
23:59:35 SCOTT@orcl> CREATE OR REPLACE PROCEDURE insert_emp(pempno number, pename varchar2) IS
23:59:45 2 stmt VARCHAR2(2000);
23:59:45 3 BEGIN
23:59:45 4 stmt := 'INSERT INTO emp_bak '
23:59:45 5 || '(EMPNO,ENAME) '
23:59:45 6 || 'SELECT :EMPNO,:ENAME'
23:59:45 7 || ' FROM DUAL';
23:59:45 8 dbms_output.put_line(stmt);
23:59:45 9 EXECUTE IMMEDIATE stmt
23:59:45 10 USING pempno, pename;
23:59:45 11 END insert_emp;
23:59:46 12 /
Procedure created.
Elapsed: 00:00:00.44
这里演示是在SYS用户下进行,如果要到指定用户执行,需要将DBMS_HPROF包的执行权限以及目录的读写权限赋予给该用户.
收集刚建立的存储过程的性能指标
00:06:11 SYS@orcl> DECLARE
00:10:42 2 v_runid dbmshp_runs.runid%TYPE;
00:10:42 3 v_plshprof_dir all_directories.directory_name%TYPE := 'LOG_FILE_DIR';
00:10:42 4 v_plshprof_file VARCHAR2(30) := 'insert_emp';
00:10:42 5 BEGIN
00:10:42 6 -- Start the profiling session
00:10:42 7 dbms_hprof.start_profiling(v_plshprof_dir, v_plshprof_file);
00:10:42 8 scott.insert_emp(9990,'Cryking!');
00:10:42 9 -- Stop the profiling session
00:10:42 10 dbms_hprof.stop_profiling;
00:10:42 11 -- Analyze the raw output and create the table data
00:10:42 12 v_runid := dbms_hprof.analyze(v_plshprof_dir, v_plshprof_file);
00:10:42 13 DBMS_OUTPUT.PUT_LINE('This Run: ' || to_char(v_runid));
00:10:42 14 END;
00:10:42 15 /
INSERT INTO emp_bak (EMPNO,ENAME) SELECT :EMPNO,:ENAME FROM DUAL
This Run: 1
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.26
执行完后,会在对应目录生成一个insert_emp的文件,直接查看文件的话,内容很凌乱也很简短,如下:
P#! PL/SQL Timer Started
P#C PLSQL."SCOTT"."INSERT_EMP"::7."INSERT_EMP"#762ba075453b8b0d #1
P#X 1331
P#C PLSQL."SYS"."DBMS_OUTPUT"::11."PUT_LINE"#5892e4d73b579470 #109
P#X 4
P#C PLSQL."SYS"."DBMS_OUTPUT"::11."PUT"#5892e4d73b579470 #77
P#X 220
P#R
P#X 2
P#C PLSQL."SYS"."DBMS_OUTPUT"::11."NEW_LINE"#980980e97e42f8ec #117
P#X 4
P#R
P#X 3
P#R
P#X 83
P#C SQL."SCOTT"."INSERT_EMP"::7."__dyn_sql_exec_line9" #9
P#X 39858
P#R
P#X 14
P#R
P#C PLSQL."SYS"."DBMS_HPROF"::11."STOP_PROFILING"#980980e97e42f8ec #59
P#R
P#! PL/SQL Timer Stopped
这里需要使用工具plshprof对其进行分析,如下:
[oracle@oracleserver ~]$ plshprof insert_emp
PLSHPROF: Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
[6 symbols processed]
[Report written to 'insert_emp.html']
[oracle@oracleserver ~]$ ls *.html
insert_emp_2c.html insert_emp_fn.html insert_emp_mf.html insert_emp_nsf.html insert_emp_tc.html insert_emp_ts.html
insert_emp_2f.html insert_emp.html insert_emp_ms.html insert_emp_nsp.html insert_emp_td.html
insert_emp_2n.html insert_emp_md.html insert_emp_nsc.html insert_emp_pc.html insert_emp_tf.html
然后我们再查看文件insert_emp.html的内容,如下:
PL/SQL Elapsed Time (microsecs) Analysis
41519 microsecs (elapsed time) & 6 function calls
The PL/SQL Hierarchical Profiler produces a collection of reports that
present information derived from the profiler's output log in a variety
of formats. The following reports have been found to be the most generally
useful as starting points for browsing:
-
Function Elapsed Time (microsecs) Data sorted by Total Subtree Elapsed Time (microsecs)
-
Function Elapsed Time (microsecs) Data sorted by Total Function Elapsed Time (microsecs)
In addition, the following reports are also available:
-
Function Elapsed Time (microsecs) Data sorted by Function Name
-
Function Elapsed Time (microsecs) Data sorted by Total Descendants Elapsed Time (microsecs)
-
Function Elapsed Time (microsecs) Data sorted by Total Function Call Count
-
Function Elapsed Time (microsecs) Data sorted by Mean Subtree Elapsed Time (microsecs)
-
Function Elapsed Time (microsecs) Data sorted by Mean Function Elapsed Time (microsecs)
-
Function Elapsed Time (microsecs) Data sorted by Mean Descendants Elapsed Time (microsecs)
-
Module Elapsed Time (microsecs) Data sorted by Total Function Elapsed Time (microsecs)
.......通过浏览器查看,我们可以点击各个链接,查看,如点击Function Elapsed Time (microsecs) Data sorted by Total Subtree Elapsed Time (microsecs)后,结果如下图:
从图可知,函数最耗时的语句为SCOTT.INSERT_EMO._dyn_sql_exec_line9(即为执行动态sql那一行),耗时39858微秒,整个函数共耗时41519微秒.
还可以点击Function Name列查看更详细的内容.
PS:其实生成的HTML大部分信息都是来自dbmshp_function_info和dbmshp_parent_child_info表.
,

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