Why am I running out of memory?

It is common to hear users say "But I have an 8GB GPU" or "But I have 64GB RAM" when a build fails. It is imperative to remember that, while terrains may seem like just simple objects, the procedural graph represents a LOT of data and this data takes up a lot of memory.

Excessive Nodes

Memory consumption increases 4X when you double the resolution.

The fewer nodes you use, the better. The higher number of nodes makes your graph more complex and slower to process. Also, each node takes up a certain amount of space. While Gaea tries to free up as much space as possible once a node is processed, it is not always possible to economize.

For a typical 8K terrain graph, if you use 20 nodes, you would have a cache size of 5-8GB. There would be some additional overhead for management and other processes. In theory,16GB RAM would be the bare minimum amount that could handle this. We recommend using 32GB to reduce the chances of paging (hard disk being used as RAM when memory runs out).

Large Resolutions

Cache size requirements increase quadratically with resolution.

While 16K may not seem like much on the surface, the sheer processing power required for a relatively complex scene can overwhelm a computer. Using the table above, we can easily calculate that 20 nodes at 16K would require 20GB-30GB of memory for actual cache and up to 96GB of memory for the overall processing and management of the build.

This is why we recommend a minimum of 64GB RAM for processing 16K builds, increasing to 128GB whenever possible.

While Gaea would recycle memory in between, there would still be some large spikes.

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For more detailed information and helpful tips on reducing memory usage, see Calculating Memory Requirements in the User Guide.