A second item that I have put together for use on assignments is a “Generic Performance Model”. This model is built as a large Excel Spreadsheet (20Mb download). Using it allows examination of how system performance may vary with user demand, time and system calibration parameters. Since it is a large spreadsheet it takes a while to re-calculate when changes are made, but it does allow useful evaluation of the likely behaviour of a system. Some caution is needed in using it as the usual IT principle of “Garbage in, garbage out” applies. I will provide documentation of the various pages of the model over the next few bulletins, or please feel free to join my web site and ask questions there.
The model may be downloaded from: Generic Performance model
Please Note: The spreadsheet comes for use “as is”. If I find, or am informed about, defects I will resolve them – then provide feedback in the forums of my web site and in the next monthly bulletin. It is, however, a complex spreadsheet which I am providing for free and so can not provide a guarantee beyond this.
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[…] Thankfully the tools needed to convert these figures into what you need are already built into a performance model. The following discussion, therefore, assume that what you will have been given is user levels and […]
[…] “Generic Performance Model” supports the analysis of a 10 year time window. In the case of a new system, therefore, this can […]