Dears,
I have just one question to clear relatively to a conclusion I can make or not when reading AWR. Let's take the following Top 5 Timed Events
Top 5 Timed Events Avg %Total
~~~~~~~~~~~~~~~~~~ wait Call
Event Waits Time (s) (ms) Time Wait Class
------------------------------ ------------ ----------- ------ ------ ----------
CPU time 356 94.5
CSS initialization 8 13 1647 3.5 Other
db file sequential READ 2,428 3 1 0.8 User I/O
control file sequential READ 4,547 3 1 0.7 System I/O
log file parallel WRITE 333 2 6 0.5 System I/O
----------------------------------------------------------------------------------
When looking to the 1 ms of Avg wait to read a single leaf block (from disk when not in cache), can I conclude that the machine has a very acceptable storage service that services a physical I/O very quickly?
And when looking to the following second example (where I have deliberately exagerated the Avg Wait(ms) times)
Top 5 Timed Foreground Events
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Avg
wait % DB
Event Waits Time(s) (ms) time Wait Class
------------------------------ ------------ ----------- ------ ------ ----------
db file sequential read 465,020 3,969 29 47.4 User I/O
DB CPU 995 11.9
db file parallel read 2,251 322 143 3.8 User I/O
db file scattered read 15,268 153 30 1.8 User I/O
gc current block 2-way 108,739 116 1
Could I also "jump" to a conclusion that those average wait time for single I/O(29 ms) or multi block reads(30 ms) are serviced by a slow storage service?
Thanks for your help
Mohamed Houri