In the past year I had lots of interactions with Blender artists – regardless of whether they are already our customers or not. It’s something I enjoy doing on a personal level, and it is also something that helps us fine-tune our farm to better suit your needs.
During these talks I was sometimes asked about what a render farm is, what it does and how could it help in delivering a project. That’s why I decided to start a mini-series of articles, in which I will try to answer some of these questions.
This first part focuses on the basic questions: the what’s and how’s of render farming.
What is a render farm?
I am turning to Wikipedia for a formal definition of a render farm: “A render farm is high performance computer system, e.g. a computer cluster, built to render computer-generated imagery (CGI), typically for film and television visual effects.”
From the end-user perspective, a render farm is a service that puts a lot of computing power at his disposal, with the purpose of helping him deliver his projects faster.
How does it work?
The process of using a render farm is pretty straightforward and it consists of just a few steps.
- The first step is sending the project to the farm. Depending on the project size and on the farm location, this step can be accomplished by simply copying a file (for a farm on your premises), uploading the file on HTTP, FTP or with a plugin, or physically sending a DVD with the project.
- The second step is launching the rendering. At this stage the farm software distributes the files to several of its computers, and they all start processing parts of the project in parallel. In order to do this, each of the computers that participate in the rendering process has its own instance of the 3D software installed and configured.
- The final step is when the user receives the rendered images or movies – the reverse operation of the first step.
Of course, depending on each farm’s software and configuration, the actual actions needed to complete each step may vary. But the general principle remains the same for all farms.
Are they all the same?
As they say, there is more than one way to skin a cat, and this goes for render farms as well. They all do the same basic thing, but the way they can do it can be different. Let’s see the ones that are typically available to end users:
Collaborative (or publicly distributed). Their network of computers is supported by users – each user needs to make his machine available for rendering other projects. In turn, he is allowed to render his own projects on everybody else’s machines. Collaborative farms require a moderate level of tech skills to use.
Home-built. The user has several computers at home and uses them together to complete the rendering. They require a high level of tech skills to set up and use and, in some cases, programming is required.
Cloud/Datacenter based. They use servers from datacenters for the rendering. Because of that, they are the most stable option. They also require the lowest level of tech skills to use.
How does it help me?
Using a render farm has a few advantages, out of which speed, convenience and risk mitigation are the most important ones. I’m going to briefly explain each one:
Speed. Having a project rendered on several servers in parallel means that it will finish faster. The speed boost can vary depending on a lot of circumstances, and it can go from two times to hundreds of times faster. The most spectacular results are, of course, when rendering animations: imagine rendering on 150 servers, each server being 3 times faster than your MacBook Pro. That sums up to a whooping 450 times faster. Or 1 hour instead of 18 days of rendering.
Convenience. When you send a project to a farm, you free your own computer. This means that you won’t have a constant source of noise and heat running 24/7 in your house or office. And it also means that you can use that computer to do other work. Or to play that great game you never have the time to finish.
Risk mitigation. Computers can overheat and shut down, or even break. Or the job could get cancelled due to a power failure. And it’s even worse if this happens on the night before the project deadline. Render farms deal with these events in a safe way for the user. Even when a server breaks or the power goes out, the rendering is moved to another machine. This means your renders will always be ready when you need them.
That’s what a render farm is and what it does. In the next article, I will discuss what you need to know to start using a reder farm. If you have specific questions or related topics you would like us to treat, put them in the comments and we will try to find the answers.
Related articles on render farms:
1. Start using a render farm
2. Render farms costs & pricing
3. Render farms pro’s and con’s
4. How does a render farm work
