Good language to develop a game server in?

Question

I was just wondering what language would be a good choice for developing a game server to support a large (thousands) number of users? I dabbled in python, but realized that it

Answer 1

I might be going slightly off-topic here, but the topic interests me as I have (hobby-wise) worked on quite a few game servers (MMORPG servers) - on others' code as well as mine. There is literature out there that will be of interest to you, drop me a note if you want some references.

One thing that strikes me in your question is the want to serve a thousand users off a multithreaded application. From my humble experience, that does not work too well. :-)

When you serve thousands of users you want a design that is as modular as possible, because one of your primary goals will be to keep the service as a whole up and running. Game servers tend to be rather complex, so there will be quite a few show-stopping bugs. Don't make your life miserable with a single point of failure (one application!).

Instead, try to build multiple processes that can run on a multitude of hosts. My humble suggestion is the following:

• Make them independent, so a failing process will be irrelevant to the service.
• Make them small, so that the different parts of the service and how they interact are easy to grasp.
• Don't let users communicate with the gamelogic OR DB directly. Write a proxy - network stacks can and will show odd behaviour on different architectures when you have a multitude of users. Also make sure that you can later "clean"/filter what the proxies forward.
• Have a process that will only monitor other processes to see if they are still working properly, with the ability to restart parts.
• Make them distributable. Coordinate processes via TCP from the start or you will run into scalability problems.
• If you have large landscapes, consider means to dynamically divide load by dividing servers by geography. Don't have every backend process hold all the data in memory.

I have ported a few such engines written in C++ and C# for hosts operating on Linux, FreeBSD and also Solaris (on an old UltraSparc IIi - yes, mono still runs there :). From my experience, C# is well fast enough, considering on what ancient hardware it operates on that sparc machine.

The industry (as far as I know) tends to use a lot of C++ for the serving work and embeds scripting languages for the actual game logic. Ah, written too much already - way cool topic.

Answer 2

What kind of performance do you need?

twisted is great for servers that need lots of concurrency, as is erlang. Either supports massive concurrency easily and has facilities for distributed computing.

If you want to span more than one core in a python app, do the same thing you'd do if you wanted to span more than one machine — run more than one process.

Answer 3

More details about this game server might help folks better answer your question. Is this a game server in the sense of something like a Counter Strike dedicated server which sits in the background and hosts multiplayer interactions or are you writing something which will be hosted on an HTTP webserver?

Personally, if it were me, I'd be considering Java or C++. My personal preference and skill set would probably lead me towards C++ because I find Java clumsy to work with on both platforms (moreso on Linux) and don't have the confidence that C# is ready for prime-time in Linux yet.

That said, you also need to have a pretty significant community hammering on said server before performance of your language is going to be so problematic. My advise would be to write it in whatever language you can at the moment and if your game grows to be of sufficient size, invest in a rewrite at that time.

Answer 4

It may depend a lot on what language your "game logic" (you may know this term as "business logic") is best expressed in. For example, if the game logic is best expressed in Python (or any other particular language) it might be best to just write it in Python and deal with the performance issues the hard way with either multi-threading or clustering. Even though it may cost you a lot of time to get the performance you want out of Python it will be less that the time it will take you to express "player A now casts a level 70 Spell of darkness in the radius of 7 units effecting all units that have spoken with player B and .... " in C++.

Something else to consider is what protocol you will be using to communicate with the clients. If you have a complex binary protocol C++ may be easier (esp. if you already had experience doing it before) while a JSON (or similar) may be easier to parse in Python. Yes, i know C++ and python aren't languages you are limited to (or even considering) but i'm refer to them generally here.

Probably comes down to what language you are the best at. A poorly written program which you hated writing will be worse that one written in a language you know and enjoy, even if the poorly written program was in an arguable more powerful language.

Answer 5

You could also look at jRuby. It comes with lots of the benefits of Java and lots of the benefits of Ruby in one neat package. You'll have access to huge libraries from both languages.

Answer 6

You could take a look at Stackless Python. It's an alternative Python interpreter that provides greater support for concurrency. Both EVE Online's server and client software use Stackless Python.

Disclaimer: I haven't used Stackless Python extensively myself, so I can't provide any first-hand accounts of its effectiveness.