Re: storage service times

From: John Kanagaraj <>
Date: Thu, 3 Jan 2008 14:00:59 -0800
Message-ID: <>


> A lot of ifs go with this but:

One of the "ifs" is this: If your CPU run queue is high (i.e. there is CPU congestion), then your Wait times will also be inflated. This occurs (roughly) because Oracle cannot understand or differentiate between "Time spent waiting for I/O" and "Time spent in the RunQ waiting for CPU", and thus shows the wait time as the difference between the time the process requested I/O and the time it came back into the CPU. (This is one reason why the "CPU" component shows up as "CPU + Wait for CPU" in the ASH Report. )

So *if* the CPU runq is high, I wouldn't worry about larger than usual average wait times...

John Kanagaraj <><
DB Soft Inc (Sorry - not an Oracle blog!)
** The opinions and facts contained in this message are entirely mine
and do not reflect those of my employer or customers **
Received on Thu Jan 03 2008 - 16:00:59 CST

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