Subject: SD beginner : immaterial flow modeling for computer science topic ?

Posted by Eric Stiens on 6/16/2010
In Reply To:SD beginner : immaterial flow modeling for computer science topic ? Posted by Michel Lutz on 6/16/2010

Message:

Hi Michel,

This type of question may be better posted on the SD forums here http://www.systemdynamics.org/forum/

In answer to your question, there are a variety of ways of modeling it, but I would make "current CPU capacity" a constant with whatever units you want, then have a level/stock of CPU usage with a biflow (change in CPU usage) and then derive the dimensionless percent value from that

[CPU usage/CPU capacity] * 100 = Percent CPU usage

You could have the percent usage effect various other values as well as of course effect the "change in CPU usage" to make sure CPU use never goes over capacity

This would allow you to do things later on like vary the CPU capacity, etc, as well as be best practices as far as units, etc go.

Eric