You could very well be tuning for the wrong thing here. What I want to see is the DURATION of all those batch/maintenance/SSAS jobs. Did things process more quickly in total or less quickly? With the servers not being accessed except by batch jobs I want my CPUs running at 100% where possible as long as that makes all jobs finish more quickly in total.
Also, at virtually every client I do performance reviews at they have overlapping jobs, sometimes tens of them running at the same time! There are 60 seconds per minute, 60 minutes per hour and X hours in your maintenance window. Use them!! Spread out the batch activities and you can see total runtimes reduce by an order of magnitude in some cases!
Kevin G. Boles
SQL Server Consultant
SQL MVP 2007-2012
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