add v-processor to running SQL server

Hello,

if I remember correctly adding virtual processors to running SQL server could be tricky from performance point of view.

May be I mistaken and there is absolutely no problem...

I am setting up SQL 2012 on Server 2012. Can I be that there will be no impact in the future if I will start with 1 processors and lets say in two month I will add second one if necessary and in 6 month I will add 2 more to bring it to 4 if necessary.

Basically, it is general question: can I add processors to SQL server if required.

What are best practice? I know that playing with processor affinity is a bad idea.

Thanks.

"When you hit a wrong note it's the next note that makes it good or bad". Miles Davis