I have a 8GB RAM Linux server which will be running Apache and mysql. First I was thinking of chrooting mysql (and apache) but then thought of putting mysql in a virtual machine on the same server, say a kvm guest with enough RAM dedicated to it (e.g. half, or 4GB). One reason was that this solution - provided that the kvm guest host has gone through the Linux hardening process - would be more secure than having a regular chroot. But I thought another reason would be to make the setup more "stable" in the sense that mysql would not interfere with apache as much as when both are on the same server. I mean, even if they are both on a same physical server, keeping mysql in a separate virtual machine surely would make memory, cpu, etc more controllable. Is this a recommended setup? Also, would mysql performance suffer from having it inside a VM?
Edit: debian 64 bit, kernel 3.7.4, dedicated server with nothing else on.