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Message Posted: Fri, 10 Nov 2006 @ 19:21:16 GMT

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Hi Srikanth,

If you are asking how to know ahead of time what the relative weight for a given allocation group will be, it will depend on what is active at any point in time and what assigned weights you have given to it and to other components.

Here is the actual formula used by Priority Scheduler to determine relative weight, which is based only on active resource partitins (RP) and active allocation groups (AG):

     RelWt (AG) = Wt (AG) / TotWt (RP's AGs) * Wt (RP) / TotWt (RP)

If you are asking about how to appropriately select the assigned weights when you are using multiple performance periods within a performance group, that will depend on the priority differences you want to achieve between the allocation groups.

If you are designing query milestones, for example, it is usually a good idea to have a strong contrast in assigned weight from the first allocation group to the second allocation group, like a 3:1 ratio or a 4:1 ratio. Priority scheduler usually performs more effectively if you seeking differences in performance when there are fewer allocation groups active (6 to 8) with larger contrasts between their weights, as opposed to lots of active allocation groups (12 or 15) with small differences between them.

I believe query milestone are more effective with fewer demotions(two allocation groups only) with larger contrasts between the weights of the two allocation groups (as an example, a weight of 20 and a weight of 5 for example).

Thanks, -Carrie

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