Memory Usage Question

I’m wondering if anyone can help me figure out why this situation would occur. We have 2 Rhino stations - 1 has an i5 cpu (gen 3) with 32 GB ram and one has an i3 (gen 4) with only 8gb ram. If I open the exact same model on both machines, the i5 machine with the 32GB ram is using almost 12GB ram and the i3 machine with the 8GB ram is only using 1.2. On both machines, this is the only program running. Is this something where Rhino will actually use more if more is available?
By the way, if there is a specific hardware forum where this should go, please direct me, but I could not find one.

Hi Stephen - is that Rhino memory usage or overall usage? I suspect the latter , right? and I guess that is due to Windows managing memory usage for the system - just a guess…


Actually it is Rhino usage. Rhino is the only program running on both machines and Task Manage confirms that it is Rhino using all the memory. And it really is the exact same model that was copied from one computer to another.

Hi Stephen - hmmm… do both Rhino’s have the same plug-ins loading and are they both using the same display modes when you check?


I don’t have any plug-ins and they are both set to “shaded”. I checked to make sure there were no unused blocks in each one and I tried a “save-small”, but no change. I even shut down both systems, restarted them, and opened the same model and I am getting the same thing. The system with the more ram is using more ram.

I did a quick look in the task manager comparing R5 with R6.

I saved out an R5 model from R6 and opened it in R5. The memory usage is nearly double in R6 - with exact same display settings, with only a 50MB STL in each file:

Memory (Private Working Set) from Task Manager
Rhinoceros 5.0 (64-bit) 337,376 K
Rhino WIP (also 64-bit) 644,448 K

Just posting for comparison. I have 32GB of RAM to play with on most of my machines.

But both of my machines have 5 and it is the exact same model. Still cannot figure out why one machine uses so much memory and the other doesn’t.

Hi BW1 - what about a new session with a default template, and no objects… ? Of course plug-ins will come into it as well - here, 5 takes more ram just to be open but I do have a pile of plug-ins.


Totally blank default workspace R5 = 164,420 K

Totally blank default workspace R6 = 179,740 K

Interesting…not much difference in this case.

Same workspaces; Import 50MB Binary STL:

R5 = 276,540 K
R6 = 263,980 K

Makes no sense to me!

Hi BW1 - if you did anything with the mesh in your first comparison post above, the undo stack would grow by adding the mesh- do two things and add two meshes…


Thanks Pascal - but no. I didn’t even choose a scale template when starting up each. I hit the X on the startup choices screen. Then blank default workspace on each. File->Import->STL and that was all. Absolutely no other commands used - nor transformations. I didn’t ‘touch the screen’ with the mouse or move anything.

So, it doesn’t look like much RAM difference between the two. I think maybe this was the case with the Undo Stack with my original response @ 2x RAM on R6.

Somehow the thread got hijacked, but I did find an answer to this and many may find it interesting. As I had mentioned, the computer with only 8gb ram used only about 1.2 to open a model. This same model used about 12GB on a machine that has 32 GB ram. So I moved 16gb from one computer to the other, which took the machine with 8 up to 24. Now when I open that model on that machine, it uses 11gb as opposed to 1.2. So the only conclusion is that Rhino will use more ram if it is available. If there is less ram, it will use less, but still open the model.