How to configure the server to work with a large number of users?

Question

Server optimization

Hello!
Need advice and solutions to optimize the web server, how to make the server withstand online 3000-5000 users, and how to speed up its work?
Server:
Processor - Intel Xeon E3-1245V2
Memory - 16 GB DDR3
Installed php 5.6
DBMS - MySQL
Web server - Apache
Already enabled caching, compression.
In short, it is necessary that the server does not fall under heavy loads and can withstand a large online well, and also be faster.
(how to optimize Apache, PHP, MySQL and other server settings?)

Answer 1

This is a big job, and no one, in a nutshell, in answering a question, will help you do it.
You have to look at your specific situation, look for bottlenecks and eliminate them...
There is simply no optimization for all occasions.
From general recommendations:

• If possible, you should switch to php 7+. This can give a noticeable performance boost.
  
• It might be better to get rid of apache.
  

Answer 2

3000-5000 per day? it's not a burden at all.
3000-5000 at once? it is necessary to completely cut the architecture under the speed if you want performance guarantees. you should contact a qualified programmer . he will look inside and say / redo.
general advice here will not help.
here only general aspects are described in the article - and already a whole article
From the shit code to Highload. We use TARANtool. 5 p ...
in a short answer, well, there’s no way to answer.
To begin with, I would suggest profiling to find out where exactly it slows down.
provided that before that all the trash, similar to the one described in the article, has already been cleaned up.

Answer 3

To begin with, abandon Apache and switch completely to NGinx
In general, it's not a fact that a dedicated server will work well. Are you sure the hardware is good? Maybe the horse is dead...