@Skynet_india hello sir, if you mean you created a physic loop by connecting two ports to a hub, and the CPU usage is normal, please notice that MSTP is enabled by default on switch, this will make one of the interface under discarding state, if you wanna a real loop, you can try diable stp on the switch and send a broadcast packet into switch, by then, check the CPU usage, you should get a high CPU usage.
by the way, please DO NOT try this in real network.