Blender 2.8 performance + Cycles speed

Hi there,

I’m testing Blender 2.8 and I’m impressed. Overall, the feeling is that I can be productive and get my work done quite fast. I also used to use older versions in the past (from old 2.3xx to early 2.7).

Now I’m having a problem with some scenes in terms of performance. When I deal with heavy, dense, models Blender can get slow, and sometimes I mean really slow to a point where switching from object to edit mode can take minutes. Or trying to create vertex groups also can take a lot of time. And when I’m finally able to create a vertex group trying to rename the group it reveals to be a very difficult task. I double click on the group’s name but nothing happens. If I wait (a lot), then, maybe, eventually I’m able to rename it. And the UNDO is affected as well (turning off the global UNDO doesn’t seem to fix the issue).

The other question is about Cycles. I love the quality and I’ve been able to get very, very close to some of the renders I do with Redshift. That said, the amount of time to get the render is more than twice, sometimes three times. And noise-wise I’m not close.
I know when it comes to speed up the render there are several aspects to take into account. I have a relatively good understanding of sampling, and how to optimize a render. I’ve used Arnold, Vray, Mental Ray, Octane and now Redshift and with all these render engines I’ve been able to get great results in quite a short amount of time. Even though I’ll keep watching tutorials and read about Cycles and how to squeeze the most of out it in the least amount of time, I have the feeling I won’t be able to improve the rendering times that much. Granted, Redshift is probably one of the fastest render engines on the market today, so saying that Cycles takes twice or three times to render the same scene is not a bad thing per se.
I’m only wondering if, besides the limitations of my skills related to Cycles, there’s some speed improvement being considered and/or planned for future releases. At some point, I’d love to render a short animation using only Blender+Cycles.

Sorry for the long post.

Keep up the amazing work!
I thought I would keep using my old 2.7 for my modeling needs only. 2.8 changed my mind along with all the amazing works the community does with your great tutorials, addons, and contributions.


I guess I’ll wait and I’ll find out by myself :grin:

There’s a ticket on performance regressions and undo performance.

As far as the cycles/redshift comparison is going I’m not qualified enough to address that, but it holds up very well compared to Arnold, Mantra and many other unbiased pathtracers.

There’s RTX support coming, and the new denoiser should help. Not sure, rendering speed is not a big bottleneck in my pipeline.

Regarding Cycles, maybe ckeck out E-Cycles. It apparently comes with some big speed improvements.

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Thank you both for replying.

I’m glad to see that both the performance and the undo issue have already a ticket.

As for Redshift, I’m doing some test myself and I’m getting mixed results. But speed aside, I’m liking the results with Cycles.

As for the E-Cycles version, my understanding is that is not an addon but an actual build itself. For now I’ll stay with the regular version.