MMORPG: The Problem of Saving State

By Deane Barker on November 15, 2012

The game Glitch is shutting down.  This game was never really out of beta, and it was one of those “explore the world” type games.  By all accounts, it was amazing, but they couldn’t make it profitable.

They have a FAQ about the shutdown, and it includes this question which I found interesting from an engineering perspective.

Why don’t you give the game away or make it open source or let player volunteers run it?

Glitch looks simple, but it is not. Any massively multiplayer game is several orders of magnitude more complex than a multiplayer game (and those are usually an order of magnitude more complex than a single player game). The state of the world changes hundreds of thousands of times a second, and each of those changes has to be immediately saved in a way that is safe and redundant. Most of those changes — decrease in a chicken’s lifespan, the regeneration of a rock, the health of a tree, the movement of every player — have to be sent from server to server and from server to player’s local computers. If you’re in a busy place in Glitch, your computer might be receiving hundreds or even thousands of messages about stuff that’s happening around you every second.

It takes a full-time team of competent engineers & technical operations personnel just to keep the game open. Even if there was a competent team that was willing to work on it full time for free, it would take months to train them. Even then, the cost of hosting the servers would be prohibitively expensive.



  1. Amazing? There was lots of hype about how you’d be able to change the world, learn skills, build things collaboratively. But it was a pretty grind game – an animated farmville without the Facebook connection.

Comments are closed. If you have something you really want to say, tweet @gadgetopia.