Is it slower to employ “name-based” hosting of multiple websites on one VPS?

Question

Assuming traffic/server load is not a factor ...

(Taken further, we could even assume that there are zero visitors, and I just happen to visit one of my websites in a "vacuum")

... Would there theoretically be any difference in the loading time if I were to host only a single site on my VPS vs. hosting multiple sites using the "name-based" method?

(Even if it is minuscule, I would still like to know—and why, ideally!)

Answer 1

So there are a tons of different ways to look at this, most importantly is what type of applications are running.

What I mean by this is if your running a static webpage for each and using simple domain based routing (nginx or apache) you will see no difference , other than added disk space.

On the other hand you could be running more advanced web applications, for most cases (provided traffic is not a factor) when a request is made to the web server processes it and returns the response, only using possessing time during the request. This also will see no difference.

But! When the application requires added programs and background processing you will see a performance difference minuscule but as you add more "domains" you will see greater performance hit.

Static Pages: No difference (besides disk space)
Web Applications : Difference based on non-request based processing

You are asking what is at the root of shared hosting. Which is amazing for static and basic programs but not so good when you scale it up to larger applications.

Sidenote: This is assuming the applications are not of different run-times and requirements thus having a python + mySql and a node.js + MongoDB at the same time on a weak server would see a performance hit as the services are always running