逻辑读写深入分析.pdf

347

36页

3次

2021-01-15

5墨值下载

http://www.acoug.org

- 1 -

Oracle

Fuyuncat

http://www.acoug.org

1.0 2010/5/20

http://www.acoug.org

- 2 -

Oracle IO DBA

Oracle

Oracle Buffer Cache db block gets

consistent gets v$sysstat v$sesstat v$mystat session

logical reads db block gets consistent gets

SQL

1. HELLODBA.COM>select n.name, s.value from v$sysstat s, v$statname n

2. 2 where s.statistic#=n.statistic# and n.name in ('session logical reads', 'db block gets',

'consistent gets');

4. NAME VALUE

5. --------------------------------------------------- ----------

6. session logical reads 21827727

7. db block gets 7786654

8. consistent gets 14041073

db block gets Current Mode

buffer cache consistent gets

UNDO db block gets

consistent gets Oracle 10200 consistent gets

buffer cache Pin

buffer cache pin Oracle fixed table

x$kcbsw pin x$kcbwh pin

SQL

1. HELLODBA.COM>select kcbwhdes, sum(why0+why1+why2), sum(other_wait)

2. 2 from sys.x$kcbwh w, sys.x$kcbsw s

3. 3 where w.indx=s.indx and w.inst_id=s.inst_id

4. 4 group by kcbwhdes

5. 5 having sum(why0+why1+why2)>0 or sum(other_wait)>0;

of 36

5墨值下载

关注