Nell'esempio che segue, il DB Time speso in "database user-call" è 463909, mentre il tempo di attesa sull'evento "PX Deq Credit: send blkd" è 222393.
%Total Call Time of PX Deq Credit: send blkd => 222393/463909*100 = 47.9
Top 5 Timed Events Avg %Total
~~~~~~~~~~~~~~~~~~ wait Call
Event Waits Time (s) (ms) Time Wait Class
------------------------------ ------------ ----------- ------ ------ ----------
PX Deq Credit: send blkd 1,555,214 222,393 143 47.9 Other
db file scattered read 1,878,085 30,323 16 6.5 User I/O
db file sequential read 3,073,012 17,900 6 3.9 User I/O
CPU time 17,118 3.7
db file parallel read 203,998 6,165 30 1.3 User I/O
-------------------------------------------------------------
-> Total time in database user-calls (DB Time): 463909.1s
-> Statistics including the word "background" measure background process
time, and so do not contribute to the DB time statistic
-> Ordered by % or DB time desc, Statistic name
Statistic Name Time (s) % of DB Time
------------------------------------------ ------------------ ------------
sql execute elapsed time 462,631.7 99.7
DB CPU 17,117.8 3.7
parse time elapsed 410.4 .1
sequence load elapsed time 392.7 .1
hard parse elapsed time 220.0 .0
PL/SQL execution elapsed time 8.3 .0
connection management call elapsed time 5.0 .0
PL/SQL compilation elapsed time 2.1 .0
failed parse elapsed time 1.0 .0
hard parse (sharing criteria) elapsed time 0.6 .0
hard parse (bind mismatch) elapsed time 0.2 .0
repeated bind elapsed time 0.1 .0
DB time 463,909.1 N/A
background elapsed time 2,561.9 N/A
background cpu time 806.3 N/A
-------------------------------------------------------------
~~~~~~~~~~~~~~~~~~ wait Call
Event Waits Time (s) (ms) Time Wait Class
------------------------------ ------------ ----------- ------ ------ ----------
PX Deq Credit: send blkd 1,555,214 222,393 143 47.9 Other
db file scattered read 1,878,085 30,323 16 6.5 User I/O
db file sequential read 3,073,012 17,900 6 3.9 User I/O
CPU time 17,118 3.7
db file parallel read 203,998 6,165 30 1.3 User I/O
-------------------------------------------------------------
-> Total time in database user-calls (DB Time): 463909.1s
-> Statistics including the word "background" measure background process
time, and so do not contribute to the DB time statistic
-> Ordered by % or DB time desc, Statistic name
Statistic Name Time (s) % of DB Time
------------------------------------------ ------------------ ------------
sql execute elapsed time 462,631.7 99.7
DB CPU 17,117.8 3.7
parse time elapsed 410.4 .1
sequence load elapsed time 392.7 .1
hard parse elapsed time 220.0 .0
PL/SQL execution elapsed time 8.3 .0
connection management call elapsed time 5.0 .0
PL/SQL compilation elapsed time 2.1 .0
failed parse elapsed time 1.0 .0
hard parse (sharing criteria) elapsed time 0.6 .0
hard parse (bind mismatch) elapsed time 0.2 .0
repeated bind elapsed time 0.1 .0
DB time 463,909.1 N/A
background elapsed time 2,561.9 N/A
background cpu time 806.3 N/A
-------------------------------------------------------------
Ho notato che esiste una piccola discrepanza tra il "DB Time" riportato al top del report AWR e quello riportato più sotto nello stesso output. Infatti
Snap Id Snap Time Sessions Curs/Sess
--------- ------------------- -------- ---------
Begin Snap: 9671 10-Aug-11 00:00:24 151 2.3
End Snap: 9676 10-Aug-11 05:00:27 156 2.2
Elapsed: 300.04 (mins)
DB Time: 7,731.82 (mins)
mentre
-> Total time in database user-calls (DB Time): 463909.1s
7731 minuti sono 463860 secondi (7731*60 ). La discrepanza è di 49 secondi.
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