#Reedited The answer has been put at the end of the question (the Summary part).

#Qutstion I'm trying to disable some CPUs of my server.
I've found this link: https://www.cyberciti.biz/faq/debian-rhel-centos-redhat-suse-hotplug-cpu/linux-turn-on-off-cpu-core-commands/, which offers me a method as below:

Here is what numactl --hardware gave me:

I want to disable all CPUs from 16 to 63, so I write a script named opCPUs.sh as below:

#!/bin/bash

for i in {16..63}; do
        if [[ "$1" == "enable" ]]; then
                echo 1 > /sys/devices/system/cpu/cpu$i/online
        elif [[ "$1" == "disable" ]]; then
                echo 0 > /sys/devices/system/cpu/cpu$i/online
        else
                echo 'illegal parameter'
        fi
done
grep "processor" /proc/cpuinfo

Then I execute it: ./opCPUs.sh disable and I can see the result of grep in the script:

It seems to work.

Now I think all of processes should be in CPU 0 - 15 because others have been disabled.
So I use the existing processes dbus to verify as below:
ps -Lo psr $(pgrep dbus)

I get this:

The psr tells me in which CPU the process is running, right? If so, I have disabled CPU 60, CPU 52 etc, why they are still here?

set isolcpus = 4 in grub and reboot can disable the 4th CPU permanently;

echo 0 > /sys/devices/system/cpu/cpu4/online can disable the 4th CPU, the 4th CPU will still keep working for the processes that have already been assigned to it but no new process will be assigned to the 4th CPU anymore;

taskset -c 3 ./MyShell.sh will force the MyShell.sh to be assigned to the 3rd CPU whereas the 3th CPU can still accept other processes.