If the system is batch-centric or batch processing is the priority, the situation becomes very different. For systems focused on batch processing, service levels are not measured by response time. The key service level for batch systems is throughput; that is, response time is not based on a single batch job, but on a group of batch jobs. Put another way, throughput is important, not response time. Idle resources are death to throughput. For a batch-focused system, every bit of CPU power needs to be consumed.

The way to ensure every bit of CPU is being consumed is to ensure the CPU busyness reaches the level where there is always a process waiting in be serviced. Said another way, make sure there is always a process queued up and ready to run. So for a batch-centric system, you will want to run the CPU busyness at a much higher level than you would for an OLTP-centric system.

Don't get carried away during batch processing times and allow a massive queue, because the operating system must manage processing scheduling. The longer the queue, the more time the operating must spend managing the queue. The key is to ensure there is always a process ready to run, not a hundred processes ready to run.