File Opens Excruciatingly Slowly


Long time Rhino user, new forum member.

I have a question about a file that I am working with right now. It is opening so incredibly slowly on my machine even when I am working on it from my SSD. Sometimes is takes as long as 5 minutes or more to open or will simply lock up and I have to close Rhino and start again. Is there somewhere to submit files for testing? Or a way to inspect it for why it is so slowly beyond the Audit command?

The file is only ~270Mb and I have had files over 1Gb that have not been as bad to use. It does make heavy use of block instances (which is the only real difference from my usual workflow), but I had set it up that way thinking that blocks are lighter in terms of memory usage.

Audit Summary:
Table tally:
79 layers
29 instance definitions
10 dimension styles
3 fonts
8 linetypes
249 rendering materials
Object tally:
44771 normal objects
0 locked objects
0 hidden objects
0 deleted objects (in undo buffer)
8072 block definition objects
0 reference normal objects
0 reference locked objects
0 reference hidden objects
0 reference block definition objects
No errors.

The only other thing that I can think of is that there is a lot of imported GIS and AutoCAD linework that is perhaps causing problems. I have just purged the file, saved and reopened and it hasn’t helped. While opening, it shows Rhino using about 10% CPU and ~6Gb of ram.


Please take screenshots of two pages in Options:
Annotation, and Annotation>Linetypes

Hi Tykom -
Blocks may be more efficient but only if they replace repeated objects - one definition for any number of instances. Not sure what you have here but that is a lot of definitions - is each of these representing a lot of objects? If not, there is no efficiency - on the contrary, display may slow right down since there are some complex calculations for knowing where to show the instances.


Screenshots attached.

Most of the blocks are representing apartment types that are repeated and then nested into another block representing the building that they are a part of. The blocks of the buildings are usually repeated but there are a couple unique ones.

Nope, What I was thinking might be the cause should not be with those settings.
We may need the file to figure it out.


We are experiencing something similar recently as it’s taken one of our users ~15 minutes to open a file using Rhino 6 and license from the Zoo (also 6). Was there any updates from John, Pascal or Tykom on this?

Thanks in advance.

Hello - does the command line have any message as the file opens?


Hi, I will work with the user this morning and see what they say. Thanks

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