fluent mapping ,map a one to many for best performance

Question

i need to map a one to many relation between something that look like this

public class Foo : Bar
{
    //some simple type properties
}
public class Bar : EntityBase
{
    public virtual IList<Foo> Foos {get;set;}
    //some simple type properties
}

i want the best performance.. what is the way it should be mapped and how the table/s will look