Do multiple references impact render time?

[shawn_kearney]

We're trying to get our node graphs under control at my office, and I am wondering if I reference the same network multiple times in a shader network will this affect performance? I am assuming that reference shaders are only evaluated once?

Also, how does the cache node fit in here? Should I place the cache on the outbound FROM the reference, or is it ok to place the cache inside the reference?

[Stephen.Blair]

References aren't going to affect performance.

And if you're using these references in shaders applied to different objects, then the cache node won't help.

If you're connecting the output of a reference to multiple inputs, all in the same shader tree, then a cache node might help. Especially if this is in a volume shading tree.

[shawn_kearney]

Thank you @Stephen Blair. Specifically I am asking if multiple references to the same shader within another shader would affect performance:

Will both setups perform similarly?

[Stephen.Blair]

There's no difference between those two. After translation to Arnold, you end up with the exact same shader tree.