1. A preemptive write back system comprising: a preemptive write back controller configured to initiate a memory system to perform a write back operation such that to avoid exceeding an optimal maximal threshold of utilization of a portion of a computer system, wherein said preemptive write back controller includes: a list for storing a plurality of pointers, each pointer representing a write back memory location candidate of said memory system, wherein said preemptive write back controller initiates said memory system to perform said write back operation by selecting one of said plurality of pointers of said list.