How much RAM does a VPS need?

Question

PHP

Friends, there is a VPS with 256Mb of RAM. It's currently running Debian 8.0 x86_64 and OpenVPN, the panel shows:
120.2 MB of 256 MB Used / 135.8 MB Free
Will I have enough RAM if I install apache + php + mysql?
The load on the server is supposed to be scanty - a bot in php for telegram.
If absolutely necessary, you can abandon mysql and store data in files.

Answer 1

Will the remaining RAM be enough if I install apache + php + mysql?

In order for it to start - I think it's enough.
Why do you need Apache or even a web server? Run the script from the console. You can try PHP's built-in web server .
With a strong need, and in its absence too, you can abandon MySQL and store data in SQlite3 .
PS

panel shows: 120.2 MB of 256 MB Used / 135.8 MB Free

The only thing that confuses me is how and why you managed to screw the panel onto a server with 256MB of RAM :)) But... this is basically irrelevant, just thinking out loud.

Answer 2

Why apache? Install nginx + php-fpm

Answer 3

Enough, 100%, with a small number of requests to the web server

Answer 4

Of course it depends on the configuration. But the minimum you need to take is 512 MB.
Normal requirements - from 1024 MB. Apache eats memory, so it can be thrown out in favor of nginx + php-fpm.