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* Description: Knowledge of CPU loadaverage
* Compatiablity: RDBMS 11g, 12c
* Date: 06:01 PM EST, 03/28/2017
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<1> Linux system CPU load average checking:
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|__ $ uptime
18:08:04 up 73 days, 4:48, 4 users, load average: 2.45, 1.97, 1.18
----- ----- -----
| | |________ Load average in last 15 minutes.
| |_______________ Load average in last 05 minutes.
|______________________ Load average in last 01 minutes.
<2> Traffice Analogy:
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|__ CPU is the road, and each car presents one slice of processes
>> Load average = 0, CPU = 1
============================================================================================================================================================================
EMPTY ROAD
============================================================================================================================================================================
>> Load average = 0.5, CPU = 1
============================================================================================================================================================================
_| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____
\o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/
============================================================================================================================================================================
>> Load average = 1, CPU = 1
============================================================================================================================================================================
_| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____
\o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/
============================================================================================================================================================================
>> Load average = 4, CPU = 1
============================================================================================================
_| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____
\o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/
_| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____ =============================================================================================================
\o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/
_| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____
\o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/
>> Load average = 1, CPU = 2, Load on each one = 50%
============================================================================================================================================================================
_| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____
\o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/
------------ -------------- -------------- -------------- ---------------
_| =\____ _| =\____ _| =\____ _| =\____ _| =\____ _| =\____
\o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/ \o____o_/
============================================================================================================================================================================
<3> Command for CPU core information and count:
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|__ $ cat /proc/cpuinfo
$ grep 'model name' /proc/cpuinfo | wc -l
<4> Reference - http://blog.scoutapp.com/articles/2009/07/31/understanding-load-averages
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