huge value for 'CPU used by this session' statistic in Statspack Report

From: Luis Fernando Cerri <>
Date: Wed, 30 Jan 2008 13:38:09 -0300
Message-ID: <>

Hi, folks.

Environment information: Oracle 8.1.6 on HP-UX. Statspack is scheduled to take snapshots on a hourly base.

Statspack is consistently reporting for 1-hour interval huge values for 'CPU used by this session', something between 18M and 30M. Example bellow:

Statistic                                    Total   per Second    per Trans

--------------------------------- ---------------- ------------ ------------
CPU used by this session 18,701,249 5,157.5 6,345.9

This value leads to 187K seconds, which corresponds to almost 52 hours of CPU in a box with only 4 CPUs. It worth to mention again that it is a 1-hour interval snapshot.

Another point, the delta value for this statistic increased consistently during this month to even huge values, as you can see at This graph is based on the output of a script written by me to calculate the deltas of the most representatives wait event and 'CPU used by this session' in response time, between each snapshot in a given interval.

My first thought was that my script is miscalculating the deltas. So I compared the values reported by my script and values reported by Statspack Report. They are the same for the same intervals.

Do you know what I'm missing? Any other thoughts?

Thanks for your time and attention.

-- Received on Wed Jan 30 2008 - 10:38:09 CST

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