in my view, I believe that it is because of the number of processes and applications that our machine is already running and firewall settings also already using specific protocols, since it is not only running apache as do the dedicated servers, I also believe that the cause of the speed in the web servers, is because they are dedicated and 100% configured to run specific services, that of this processing priority and network configurations in the firewalls, since the connectivity factor, when there is firewall on the way also greatly decrease the speed of applications, for security checks and access.
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– Felipe Duarte