[hugogameiro]

Instances are not equivalent to servers. Just because you have 2000 instances, you don't need 2000 servers to run it. Just like you don't have a single server per WordPress install.

For example, I have 100 Mastodon instances running using 8 VMs at https://masto.host/

I can tell you that a VM with 2vCPUs can run 30 small instances easily (CPU load average under 50%) as long as you have 1GB of RAM for each.

So, if you have a server running, I am sure you can add Mastodon to it and the only thing you will notice is the 1GB of RAM usage. If you want to install it for a small group of users, just find a sharing hosting space like mine or go with a $3 VPS and you will be more than fine.

[apeacox]

Even if you can potentially run several instances per server (with enough ram), I think that an usable one should run on a dedicated server. Considering that a Rails app doesn't run like a webserver with php installed, just like you can do with WordPress or php apps in general. Also, I suppose 1gb is required to run the instance, but it isn't known how many users can host decently.

[hugogameiro]

I think I understand what you are saying but depending on the use case it is not only usable but it runs great.

I have instances with a couple of thousands of users and it runs smoothly with shared resources.

It really depends on what you want to build. If you want to create an instance for a small specific group of people or you want to open it to the masses. I haven't tested concurrent users but I can tell you from all the instances I run, nobody ever mentioned an issue of slowing down when experiencing heavy traffic.

I have noticed that cPanel has been pushing RoR https://documentation.cpanel.net/display/ALD/Ruby+on+Rails and I haven't tested it or know of the security implications but I am pretty sure that with enough tweaking one could install Mastodon on a cPanel server with other apps running in PHP.