Average Wait and Time Waited in Sessions view

 Message from: Matt Birchall

I've been looking at the disk latency in our system and have looked at the time vs disk read values shown in SGA trace and in the Sessions view.
The Time waited and Average wait columns in the Total Waits breakdown of the Waits tab of the sessions view is a factor 10 lower than reality. The result is that my disks show an impressive 0.89 ms latency when, in reality, the value is 8.9 ms. The time waited micro is correct but the Time Waited column (presumably milliseconds?) and the Average Wait are 10X too small.
(Toad for Oracle Base 11.0.0.116)


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Historical Messages 


Author: Matt Birchall
Date: Thu Feb 09 02:19:53 PST 2012
I've been looking at the disk latency in our system and have looked at the time vs disk read values shown in SGA trace and in the Sessions view.
The Time waited and Average wait columns in the Total Waits breakdown of the Waits tab of the sessions view is a factor 10 lower than reality. The result is that my disks show an impressive 0.89 ms latency when, in reality, the value is 8.9 ms. The time waited micro is correct but the Time Waited column (presumably milliseconds?) and the Average Wait are 10X too small.
(Toad for Oracle Base 11.0.0.116)

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