Monitoring and Tuning the Shared Pool

rem
rem FUNCTION: Generate a summary of SQL Area Memory Usage
rem FUNCTION: uses the sqlsummary view.
rem           showing user SQL memory usage
rem
rem sqlsum.sql
rem
column areas                              heading Used|Areas
column sharable   format 999,999,999      heading Shared|Bytes
column persistent format 999,999,999      heading
Persistent|Bytes
column runtime    format 999,999,999      heading Runtime|Bytes
column username   format a15              heading "User"
column mem_sum    format 999,999,999      heading Mem|Sum
start title80 "Users SQL Area Memory Use"
spool rep_out\&db\sqlsum
set pages 59 lines 80
break on report
compute sum of sharable on report
compute sum of persistent on report
compute sum of runtime on report
compute sum of mem_sum on report
select
username,
sum(sharable_mem) Sharable,
sum( persistent_mem) Persistent,
sum( runtime_mem) Runtime ,
count(*) Areas,
sum(sharable_mem+persistent_mem+runtime_mem) Mem_sum
from
sql_summary
group by username
order by 2;
spool off
pause Press enter to continue
clear columns
clear breaks
set pages 22 lines 80
ttitle off

Figure 5: Example SQL Script To Report On SQL Area Usage By User

Example output from the script in Figure 5 is shown in Figure 6. In the example report no one user is really hogging the SQL area. If you have a particular user that is hogging SQL areas, the script in Figure 6 will show you what SQL areas they have and what is in them. This report on the actual SQL area contents can then be used to help teach the user how to better construct reusable SQL statements.

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