In this question I would like to ask for sharing of some experience in planning ArcGIS Server hardware part in Web mapping projects (Flex, Silverlight).
Let suppose that we are developing RIA application and deploying ArcGIS Server with services.
I have noticed that very often on the stage of early planning of GIS projects customers would like to know approximate hardware requirements for ArcGIS Server part.
Usually it sounds in these ways:
- We need to serve N editor user and M viewers of spatial data. What server do we need (CPU, RAM)? How many ArcGIS servers?
- We already have dedicated server which we are planning to use for ArcGIS Server. How many users (editors/viewers) will be it capable to serve?
It is common that on this stage you don't have access to spatial data so it is not possible to perform any tests. But we can estimate rough amount of Map/Feature and Dynamic/Cached services.
I have studied Esri System Design Strategies document but I have not found any numbers or formulas to make such rough estimation. As I understand the best precise way is to obtain at least part of the data and perform real tests.
So, what is the best practices in such situation? Is it possible to perform such very rough calculations to answer these questions without tests with real data?
May be you already faced such problems and have some experience?