Run server as one or virtualize it into two servers?
Assuming the host computer was the same... Would it be better for me to run server with apache and mysql on it w/o virtualization or would it be better to run something like Xen and run a virtual apache and virtual mysql server on the same host?
Personally I dont think there is a need to separate web and database into different virtual machines. You can run them in the same host without any problems. Just see to configure everything optimal and secure.
Also hyper-Vs like XEN would take a _LITTLE_ resource of your system, so if you want to save that too, run it under the same host!
MySQL queries will be much faster since it will be localhost, and do not have to go through the router to fetch data in a virtual machine.
why don't try both, setup system both ways, put a load, specific to your website (BB, or wordpress, or whatever you have) and see th ediiference. My guesses are that without VPPS it will work better, you never know and still you may have doubts even after you'll install based on somebody's recommendation, while if you test it you'll know for sure wha is better.
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