What will happen if you decreased number of CPUs on a Virtual machine?

decreasing CPUs may or may not affect your VM based on the traffic and load , so i think this is a very generic question as long as there is  best practice almost for most solutions now a days so please share with us the configuration and setup you use 

Hi,

If you decrease the number of VCPUs for a machine, the performance of this machine will decraese depending on the servies and applications running on this machine.

HTH

Best Regards,

Depending on your environment and how the other virtual machines are setup you might see a performance increase. As there will be less wait for CPU allocation from the hypervisor. Your cpu wait time should come down.