VMware – question regarding # of cores per virtual machine
Posted on 2011-02-10
I have a question regarding the number of cores or CPUs you can assign a virtual machine. Is there a number that would start to impede performance of the virtual machine? The company that I work for recently hired a new IT manager. He is very knowledgeable about VMware. He said that virtual machines should not have more than one core or one CPU assigned to them. He said assigning more cores can actually impede performance. We are running ESXi 4.1 and I find it hard to believe that VMware allows you to assign up to 8 processors per VM yet using more than one CPU can impede performance. The new guy has been working with VMware for years. Is this something that maybe was true in early versions of VMware but isn’t true now?
I’m fairly new to VMware and was asked to virtualize a SQL server. The physical server has two quad core processors. I don’t feel comfortable virtualizing the server and only giving it one CPU.
Is this guy correct with his assumption that you should only assign one core or CPU per virtual machine for performance reasons or is he totally wrong? Any insight or links to documentation that would prove him wrong would be appreciated (assuming he is wrong).