So I've had this Minecraft server for a long time that I just play on with friends using Hamachi. I've always used the free version of Hamachi, which only allows up to 5 players to be in the group, but I am considering buying the large version of it which can have up to 30 people. This would allow me to have more people on the server at once.
So my question is, does having more people on my Minecraft server use more of my computer power? Whenever I have my server up, my computer fan is running like crazy and it makes other games lag and stuff run slow because of all the energy it is using, so if I have more people actually on the server will it run my computer any harder?
Note: This is just a simple vanilla Minecraft server that you can download from Minecraft.net No Bukkit or anything.
Best Answer
The simple answer is Yes, having more people on a server will cause it to use up more resources, foremost RAM and secondly CPU.
The longer answer is to explain that each person on the server loads a set of the chunks around them, that is what they are looking at. If all of the people are close together then you will get overlap on these as the players will all be looking at some of the same chunks. You have mentioned straight vanilla for this so I think you can give a safe estimate of around 50-80MB of RAM per person. I have seen hosting companies that will do around 40MB per person but again, this all depends on the area the people are playing with.
As for CPU usage, this is not going to be as noticeable assuming you have relatively recent hardware (some sort of a quad core system). This may actually be an issue for you however as you are saying when the server is running it does kick up your fan. Here you can do a bit of testing to see what to expect. Open up anything that shows you some basic hardware CPU usage stats like Windows Task Manager (if on Windows). Take a look at your CPU load with no server, then with the server running, then with 1, 2, 3, 4, 5 people on the server. If there is a good impact as the number of people increase then it may be a good baseline to estimate the total number of connections you feel your system can handle. (NOTE: You can also eye the RAM changes over those steps as well to get more accurate numbers but remember the RAM used can change based on how far apart players are from each other).
Hope this helps.