Reasons a Render may Hang

[WAS]

My friend is rendering one of my canyon rock studies on his little server but he says that the render is frozen right at the end with only one block left to finish rendering. The timer is still going but he says the CPU is idle.

[Oshyan]

That's not something we see happen very often. What are the specs of the machine? Is it possible that the last tile is just really demanding for render time? How long has it been going?

- Oshyan

[WAS]

That's not something we see happen very often. What are the specs of the machine? Is it possible that the last tile is just really demanding for render time? How long has it been going?

- Oshyan

I'm not sure of the specs but he says my renders are "unusually slow" to begin with typically he finishes renders in a few hours, where mine can take all night. I think me being stuck on free, with limited resolution and antialiasing, I don't much notice my performance issues with setups.

The slowdown is on the bottom left of the image, where some fake stones are creeping the canyon wall. Do fake stones get their origin from terrain? The canyon displacement could be trying to be computed into the stones, and then almost erased with the very soft stone surface

[Oshyan]

The stones will be displacing off of whatever displacement is above them. If the upstream displacement is complex and especially if you have e.g. an additional Compute Terrain, it could be very slow for downstream displacement effects.

- Oshyan

[WAS]

The stones will be displacing off of whatever displacement is above them. If the upstream displacement is complex and especially if you have e.g. an additional Compute Terrain, it could be very slow for downstream displacement effects.

- Oshyan

No additional Computer Terrain, I've been careful about that. Just a tex coords for the coloring of the stone. It did finally finish, you can see the outcome in the Canyon Displacement thread.

I think it may be related to my complex functioning that could honestly lose some weight. Not that it's even too complex, just lots of merging and rotating.

[Dune]

That's always a pitfall, all the nodes you add to make it perfect add to render time, some more than others. Obviously, like you say, I always try to use as little as possible nodes, especially computes.