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Oracle Tips by Burleson Consulting
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Oracle server
Load Averages
At the very beginning of the top output we see a series of three
numbers. These are the called load average metrics. The load average
is an arbitrary number that describes the load on the system. The
first load average value is the immediate load for the past minute.
The next value represents the load average from 5 minutes in the
past. The third value is the load average from 15 minutes ago.
Whenever the load average rises above 1, you can assume that the
processors are fully burdened and you should immediately run vmstat
to check the runqueue values.
Here we start with information on the server load average. The load
average is an arbitrary number that describes the load on the
server. In general, a number less than one is ideal, and here we see
three load average values.
The load average display shows the load averages for the past
minute, the past 5 minutes, and the past 10 minutes. A low load
average is ideal, and the load average should stay below zero.
Whenever the value exceeds “1” there may be a CPU overload problem.
System: penguin Mon Sep 10 17:35:13
001
Load averages: 0.52, 0.38, 0.34
213 processes: 211 sleeping, 2 running
In general, the load average is the average
sum of the number of processes waiting in the CPU run-queue (plus
the number of tasks currently executing) over 1, 5, and 15 minute
time periods.
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