As the title says. Is it cpu, memory, gpu, gpu memory? And how can I find how I’m bottlenecked?
Good hardware for games, good for sculpting in Blender. So, OpenGL performance.
- GPU: Good OpenGL performance
- GPU: A lot of GRAM. (I think at least 8 GB)
- RAM: A lot of RAM. (I think at least 16 GB)
- CPU, At least 5th generation CPU.
Currently most of the sculpting process comes from the CPU. GPU has almost no influence at all in Solid mode and it is not responsible for loss of performance if you have an average GPU.
The more threads and the better single-threaded performance your CPU has, the better it will behave in sculpt mode. But something very important to keep in mind, currently Blender has its own limitations in Edit and Sculpt mode. This means that there won’t be much of a performance difference in those modes if you currently have a not very old CPU (a not very bad one), or if you have the latest high-end CPU. What is your current CPU?
The developers are constantly working on improving Sculpt and Edit modes performance, so Blender limitations may disappear in the near future.
Obviously RAM amount plays a role. If you run out of RAM and your computer starts to use virtual memory intensively then performance will decrease.
I have a Ryzen 7 2700X CPU, it has eight cores at 3,7GHz.
I also have 16GB of RAM.
My GPU is kind of old though, it’s a GTX 660 – which is why I was asking, to see if I should upgrade or if my current issues have more to do with poor planning with subdividing/remeshing.
Sculpting is based on your Viewport Performance and Viewport Performance = OpenGL Performance. If you have not good GPU with good OpenGL performance, your works always be lagging.
Your RAM is enough, GPU is average, little old. If you will meet critical lags, you can try upgrade your GPU. But don’t forget, when polygon counts increase, your performance may be decrease.
If the problem you have is not due to excessive use of RAM (you can monitor it with a system monitor while you sculpt), I am almost sure that the problem is not your hardware but Blender’s own limitations.
You could share a scene where you have noticeable performance problems in sculpt mode, so that someone with better hardware than you have can test it and tell you if he/she also has problems.
I’m not sure if you come from another sculpt program, but GPU is not that important in sculpt mode and solid view in Blender:
Unless you are using an ultrabook CPU with integrated graphics, I don’t see any other situation were in the 2.9 series sculpting will be affected by drawing performance.
If you have such a low-end GPU, you will not only have problems in sculpt mode, you should have problems in all of Blender, especially in Eevee. GTX 660 2GB vRAM should be enough for Blender Sculpt mode for 1080p monitor/screen).
GPU important for Blender. Blender is OpenGL based program and OpenGL performance is everything.
For try, use MESA OpenGL wrapper and see how your performance will decrease (never use with Eevee, only Cycles).
What I said before, if you have low-end card or bad drivers, the performance of Blender viewport is going to be bad in all respects, not just in sculpt mode. If your card can handle Blender viewport in most circumstances and you are having trouble only in Sculpt mode or Edit mode, the bottleneck is most likely not the GPU.
Sculpting needs high poly counts and this decrease your performance. If you have not good GPU, then your sculpting will be lagging. When normal using maybe you can not feel this, if you don’t work with huge scenes or polygon counts, but when sculpting, you feel this easily.
Do you know what is Vertex Buffer or polygon processing capacity? If you don’t know, then you never understand this. This is technical issue.
A GTX 660 may be old, but its not a shit GPU. I had this card and I tested many DCC’s with it as well as many games. Blender can’t keep up with other programs that run on OpenGL (Maya, Max, Houdini) so therefore its a Blender-bottleneck, not a GPU bottleneck.
Yes, not bad GPU. I used GTX 660 and 670, but when increase polygon count, then performance drastically decreased.
Maya or Max’s code design is different than Blender. Example Max use GDI for GUI, only use DirectX or OpenGL for 3D screens. But Blender use OpenGL everywhere, include GUI.
And he ask, what hardware is important? Most important hardware is GPU for Blender, exactly for sculpting.
To many users this might mean nothing. 5th gen of what?
intels core arch maybe, though I could just as well assume zen3/ryzen 5000…
I’d start by upgrading to 32gb or even 64gb if you can afford the investment.
While definitely getting long in the tooth, for openGL viewport purposes it should still be fine enough. I’d consider upgrading, yes. But for Cycles/GPGPU rendering reasons.
And again you are misinformed, while GPU performance can have some relevance in regards to rasterizing the polygons to screen…
By far sculpting in blender is a vertex data manipulation operation on the CPU side, thus heavily bottle-necked by CPU cores performance and cache size.
I am graphic programmer and today GPU not only for rasterizing. In Blender all vertex processings need GPU. Old Blender versions have “VBO” settings, today not have, because new GPUs have great VBO values. VBO, Vertex Buffer Object is a GPU architecture. When your vertex count increase, Blender needs high Vertex Buffer Size and this is occurs more transfer times RAM to GRAM. And for this reason, you begin feel lags. And Blender will needs to calculate sculpting processes for many many vertices. So, Blender needs good CPU and good GPU for sculpting operations.
These are technical issues, if you know technical infos about graphic programming, I will tell you more deep infos.
Yes gpus can do a lot more if your program is developed to take advantage of that, but blender tries to be accessible to most people, including those with older devices so they tend to stay a fair bit behind on API versions. They were originally going to target GL 3.1 and with a little convincing from the main developer behind the refactor as well as a lot of us voicing the same opinion it was finally settled on 3.3.
And even then there’s still a lot that doesn’t really take advantage of GPGPU even if it could.
Geometry manipulation happens on the CPU, and not just in edit mode.
Not important OpenGL 3.1 or 4.0 or Vulkan. This principles not based API, they are based on GPU architecture.
What is your Sculpting workflow? Do you use Dyntopo or Multires or what?
Dyntopo has not being maintained for a long time, as you can see it can perform poorly no matter how good your CPU or GPU hardware is:
But recently some improvements are planned for Dyntopo and some of them have already been incorporated in Master/Blender 2.92.0 Alpha.
Multires may have some better performance than Dyntopo, especially from Blender 2.9+, still with limitations not due to hardware. You need to have good practices with Multires, for example use a good base mesh (Low poly shaped as close to what the final sculpture will be).
You keep an eye on recent developments, developers are constantly trying to fix Blender’s own limitations.
No. Plenty of the actual sculpting, meaning the vertex deformation, and data management, happens on the CPU, and the CPU is indeed the bottleneck most of the time. You don’t need a beefy GPU to be able to fluently navigate in a scene with millions of polygons.
Try then. Use good CPU but bad GPU and view your performance.
In this case even the best cpu in the world is going to be the bottleneck.