使用shell自動化診斷效能問題(一)（r11筆記第41天）

一直以來要做效能分析的自動化工作，但是久久沒有動筆，今天索性來更新一版。

首先我希望得到的一個基本效果就是後臺去掃描資料庫的DB time，如果超出了閾值，比如這裡我設定的為400（即DB time為400%），則會開啟自動診斷的任務。時間範圍是提前一個小時和當前時間。我對已有的指令碼做了一些改動，加了一些邏輯，後續還會不斷完善。

DBTIME_THRESHOLD=400
DATE=`date '+%Y%m%d'`
BEGIN_HOUR=`date -d"1 hour ago" +"%H"`
END_HOUR=`date  +"%H"`

下面的函式會得到快照級別的DB time情況

function showsnap
{
sqlplus -s $DB_CONN_STR@$SH_DB_SID <<EOF
break on db_name
set pages 0
set feedback off
set linesize 100
col snapdate format a20
select
begin_snap
,end_snap
,snapdate
,round(((END_INTERVAL_TIME+0)-(BEGIN_INTERVAL_TIME+0 ))*24*60) duration_mins
,round((select round((sum(e.value) -
                        sum(b.value)) / 1000000 /60,2) dbtime
                        FROM DBA_HIST_SYS_TIME_MODEL e, DBA_HIST_SYS_TIME_MODEL b
                        WHERE
                         e.STAT_NAME = 'DB time'
                         and b.snap_id=begin_snap
                        and e.snap_id =end_snap
                        AND b.STAT_NAME = 'DB time'
                        group by e.snap_id,b.snap_id)) dbtime
from
(       
select
      di.db_name                                        db_name
     , s.snap_id                                         begin_snap
     ,lead(s.snap_id ,1,s.snap_id ) over(order by s.end_interval_time ) end_snap
     , to_char(s.end_interval_time,'dd Mon YYYY HH24:mi') snapdate
     , s.snap_level                                      lvl     
     ,s.end_interval_time
     ,s.begin_interval_time
  from dba_hist_snapshot s
     , dba_hist_database_instance di
 where
  ( di.dbid,di.instance_number) in
 (select d.dbid            dbid
     , i.instance_number inst_num
  from v\$database d,
       v\$instance i)
   and di.dbid             = s.dbid
   and di.instance_number  = s.instance_number
   and di.startup_time     = s.startup_time
   and to_char(END_INTERVAL_TIME,'yyyymmdd')='$1'
   and EXTRACT(HOUR FROM END_INTERVAL_TIME) between $2-1 and $3+1
 order by  instance_name, snap_id
 );  
EOF
}下面的函式會得到快照級別SQL的DB time佔比圖。
function showsnapsql
{
sqlplus -s $DB_CONN_STR@$SH_DB_SID <<EOF
break on db_name
set pages 50
set linesize 100
col elapsed_time format a10
col per_total format a10
select snap_id,sql_id,EXECUTIONS_DELTA,max_elapsed elapsed_time,per_total||'%' per_total from
(select distinct snap_id,sql_id,EXECUTIONS_DELTA,trunc(max(ELAPSED_TIME_DELTA) OVER (PARTITION BY snap_id,sql_id )/1000000,0)||'s' max_elapsed,
 trunc((max(ELAPSED_TIME_DELTA) OVER (PARTITION BY snap_id,sql_id))/(SUM(ELAPSED_TIME_DELTA) OVER (PARTITION BY snap_id )),2)*100 per_total
 from dba_hist_sqlstat where snap_id=$1
 order by 5 desc
) where rownum<=5;

EOF
}下面的函式會基於快照生成AWR報告。
function genawrhtml
{
awr_inputs=`sqlplus -s ${DB_CONN_STR}@${SH_DB_SID} <<EOF
SET FEEDBACK OFF
SET HEAD OFF
SET PAGES 0
select d.dbid||','||i.instance_number||','||$1||','||$2||',0' text
from v\\\$database d,
v\\\$instance i ;
EOF`
sqlplus -s ${DB_CONN_STR}@${SH_DB_SID} <<EOF
set pages 0
set linesize 1500
set termout on;
spool awrrpt_$1_$2.lst
select output from table(dbms_workload_repository.awr_report_html( ${awr_inputs}));
#select output from table(dbms_workload_repository.awr_report_html( `cat awr_inputs.lst`));
spool off;
set termout off;
clear columns sql;
EOF
}下面的是執行的主方法，當然還有待完善。
#MAIN 主方法

tmp_dbtime_snap=`showsnap $DATE $BEGIN_HOUR $END_HOUR|awk -v dbtime=$DBTIME_THRESHOLD '{if($8>=dbtime) print $0}' |tail -1`
echo $tmp_dbtime_snap

dbtime_snap=`echo $tmp_dbtime_snap|awk '{print $1" " $2}'`
echo $dbtime_snap
#得到快照級別的SQL佔用DB time情況showsnapsql $dbtime_snap#生成基於DB time的AWR報告genawrhtml  $dbtime_snap上面的指令碼執行很簡單，無需輸入任何引數。就會得到一個完整的資料包告。後續會透過郵件的形式來傳送。後面會繼續補充完善。