The Macbook suddenly slowed down, you may have plugged in the wrong USB-C port

The Macbook suddenly slowed down, you may have plugged in the wrong USB-C port

ndminhduc

It turns out that not every plug is the same due to the confusion and few people notice the Thunderbolt 3 / USB-C ports on the Macbook Pro. "Wrong" plugging can significantly affect the performance of the device when the operation is real.

In other words, depending on how the device is plugged in and connected to a Macbook, specifically the Macbook Pro, the performance of the device when operating will vary significantly. In one example, just plugging everything into two USB-C holes on the same side of the device will cause the device to run hotter, forcing the CPU to reduce the pulse to reduce the internal temperature, of course, performance will decrease.

Of course, this is only one of the reasons for the slow Macbook, but if in the case of a slow computer, you should check to see if it works. This story was unknowingly given by a user on StackExchange. This Adam said:

-Sometimes my computer has a task like kernel_task that runs at maximum CPU. This may take a few minutes or several hours. At this time, the machine is almost terribly slow. Restarting doesn't work either, and an up pops up until it runs itself. So what is this task?

Another user named BMike explained the phenomenon in a fairly logical way. The reason given is that connecting a number of devices to the left side of the Macbook Pro can affect the temperature in the computer. Specifically, then you may have just plugged in, and plugged in some devices at two adjacent holes located on the same side of the Macbook.

To prove this argument, Mr. BMike tracked the performance of the Macbook CPU with the "plug in and where" scenarios. Overall results:

Evidence shows that the actual CPU temperature and CPU usage tasks are not related to kernel_task. In other words, the machine is slow because the CPU has to be reduced, not the periodic No-op instruction (this is the Do not perform command!)

The iStatMenus measurement chart shows that the device that used the battery is then plugged in.

Type A: plug in one USB-C hub (mouse + key + power) and one USB-C HDMI 2.0 adapter at the same time into two USB-C holes on the left. At that time, the temperature sensor near the Thunderbolt Left Proximity will increase rapidly. After about 3-4 minutes, kernel_task appears and the CPU is used to its maximum.

Scenario B: Try to find a way to cancel kernel_task by switching the power plug from left to right. The left side temperature dropped and kernel_task disappeared after 15 seconds.

And as soon as the power plug was reverted to the left side, situation A recurred, the temperature increased rapidly and kernel_task returned after about 3-4 minutes. Continue to switch the power plug to the right, the problem is solved immediately.

Scenario C: Try plugging only Hub (mouse and key only) and the HDMI adapter into the thunderbolt port, causing the temperature to rise between 10 and 15 degrees.

In a nutshell, if you see the Macbook suddenly slowing down, trying to check the Activity Monitor might spot problems. If you find a task that is eating too many resources, like kernel_task in the above scenario, then check what is plugged in and how to plug it into your computer.

If you're using the entire port on the left to both charge your Macbook and connect to other devices at the same time, try splitting it up: switching to the right charger may help improve the situation. Similarly, don't put everything into the ports on the rightmost ports but split up.

Test results in 3 scenarios A, B and C

 

Thank you for your interest!