Many thanks to @MattW, he Help me today to move to a new server. I had a blind faith in my hosting, But I discovered today that my VPS had less than 800MB RAM when I was paying for 1.5GB ! What I like about Matt is the fact that he doesn't try to sell you anything. if you choose to stay with your hosting, its fine he can tune the server for better performance, if you want to switch hosting he give you a list of good ones. I'm having now 2GB RAM. paying less than half the price I used to pay for my old hosting. and my xenforo home page loads in less than 1.50 second . I highly recommend Mattwservices.