Tom,
When you see these oscillations, do they occur after so many generated results? Some oscillation is normal, in my opinion, from 10-15% of the performance is noise-related.
The key is to tune the server that you either 1) minimize the oscillation and/or 2)increase your overall performance above the 10-15% baseline, and 3) find out what the mean and standard deviation between all your results.
If your results are within that range, this maybe "normal". I follow-up with you later on what I do.
Steve Poe
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