Showing the response time on a graph I have several computing devices. I have used an algorithm to balance the load between these devices. There is a central coordinator which controls the load on each device and if one device is overloaded, it will transfer some load of overloaded device to a less-loaded device. I have considered the number of tasks on each device as the load of that device.

I have measured the response time with load balancing and without load balancing and now I want to show the difference between these situations on a graph. I know that y-axis represents "response time", but the problem is that I can't figure out what I should consider for x-axis. Each device may have several tasks, for example device1 = 3, device2 = 1 and device3 = 10 tasks. Should I use the mean of these values for x-axis value? If not, what should I can use for x-axis?
You Can do one thing as per my knowledge take the difference Between two response times and plot them in a line graph which ever have the more deviation from the 0 line you can say they are taking more time