# Utilization vs Percentile

My objective is to have high utilization of the resources by keeping only the required number of resources alive.

Low utilization means the resources were not used effectively, while high utilization means the resources were used efficiently. However there is a limit to the maximum utilization that one can strive for. We cannot have 100% utilization as the goal.

I have read that 75%-80% should be the ideal utilization goal for managing resources, as after 75% utilization there would be steep increase in Wait Times. Meanwhile percentiles give a good measure of the number of resources that were used most of the times. For example 75th percentile gives me the number of resources that were used for atleast 75% of the times.

How can I use these two insights to effectively measure and manage the resource capacity? What is the relationship between utilization and percentile in this case?

[UPDATE] For example can I use the difference between 100th and 75th percentile of the no. of resources as a measure of the no. of resources that are not efficiently used?

• Please don't assume readers are familiar with the context of your question - you need to explain it. – Scortchi Aug 3 '17 at 10:24
• Hi @Scortchi have updated the question. And added the relevant tags. – pauljeba Aug 3 '17 at 10:31
• You have described the relationship between percentages and utilization. I don't see how we can add any insight to that, nor how we should be able to discuss how to "use these two insights to effectively measure and manage the resource capacity". Sorry, it doesn't look like there is a statistics question in here. – Stephan Kolassa Aug 3 '17 at 10:51
• Let me rephrase the question. Please correct me if this becomes a statistics question now. "Can I use the difference between (100th and 75th percentile of the no. of resources) as a measure of the no. of resources that are not efficiently used?" – pauljeba Aug 3 '17 at 11:15