Large Assembly performance

chris_aicher

Has anybody experienced OS performance issues when working with a larger assembly?
I decided to push OS a little bit and created a large assembly.
While my other goto CAD handles it easily, it seems OS struggles.
So, what dictates the performance? Is it a hardware issue on my side, internet connection, or something else?
I placed it in public so others can have access.
Does anyone else have issues switching between tabs or getting past the loading graphics screen?

lougallo

@Rehcia We are taking a look...

kevin_quigley

I can load it fine (Safari on Macbook 15" Retina with 13MB down internet connection) but the graphic rotation is very slow/steppy. Switching tabs is OK and opening individual parts allows view manipulation at usual speeds.

What I did notice on the big assembly was when you zoom in close the graphics resolution of the curved parts is very high - which is odd as other files I have loaded are very segmented/lower res. Is this something that has changed recently?

lougallo

@Chris Aicher‌ We have identified the issue and are working on a way to better handle assemblies that have very large triangle counts (100M facets / silhouette edges etc).  This can be common when parts like fasteners are in the mix.  Currently we determine the resolution based on the complexity of the surface (high tessellations)  and would are going to improve this display mechanism.

chris_aicher

So,
Using McMaster-Carr parts may not be the best idea...

ilya_baran

@Chris Aicher‌ 
To give a little more information, what's going on is that some of the part studios (like the screws) are "simple", so we tessellate them finely.  But then they're instanced many times in the assembly, which leads to a very high triangle count and slow graphics performance.  We will need to improve this logic so we can use different tessellation quality for the same part in different tabs.  In the mean time, in the case of this specific assembly, you should be able to get much better performance by deleting the threads on the screws using "Delete Face."

chris_aicher

Thanks for the info. I made some simplified versions of the screws and it seems to have helps with the performance issues.
However, as I continue to increase the assembly size, I as getting more and more Chrome errors. Is there a "large assembly" setting or something similar?
It's getting to the point where I can't do anything w/o a crash.
Suggestions?

billy2

I opened the assembly and it doesn't seem that overly complicated. But with any design managing the dataset is crucial. 

Seems like I would want a version of this that had no electrical stuff, just sheet metal/extrusions so I could work freely on the structure and then turn on the pretty stuff when I wanted to take a screen capture. 

In SW I have many tricks to make things go away and come back so that when I'm working the system is responsive. I can't offer any thing in OS because I haven't tried to work in a large engineering layout and haven't discovered any tips on how to handle/manipulate datasets. Viewing is one thing, but selection sets/picking stuff on the screen is also important.

I did load a large assembly in OS a few months ago that I had worked on in the past in SW. I thought the display was nice and I did add some features although it was slow. Afterwards, I really thought I could use Onshape to work on that large engineering layout. I can't say how I would construct the assembly and what strategies I would use to manipulate data, but I think there's enough here for that and hopefully they add more. I don't subscribe to the notion that a CAD system must render everything all the time. I really think the solution is managing data.

We put a wafer processing plant inside SW1998 which was the largest model I've ever built. To print it out we had to use photoworks and huge frame buffer which caused the computer to access the hard drive for memory. It took the computer over night just to render the image. But during the day, because we managed the data, the system was responsive for everyday work.

In SW I used configurations mainly to manage the suppression of stuff which really reduces edge calculations, tessellation issues and slashes the size of datasets. I don't design nuts & bolts so family tables don't interest me. I used configurations to make stuff go away and come back quickly.

How do we do this on your model, here in OS, now? I don't know....

In the early days running pro/e on a pentium computer, trying to load this model you would have run out of disk space, run out of memory and killed the computer. Probably brick it and you'd never get it to reboot. I think we've come a long way.

pete_yodis

@Bill I would hope Onshape in due time will reduce the number of "tricks" we do to keep data sets workable.  OS is running on a system with far more horsepower than local installed software, and it should only scale bigger.  I think we will be able to take advantage of that, so that we can just design stuff and not spend time managing the tricks to keep the design workable.  Here's to hoping...

Ed_Danzer

@Chris How many parts are in this assembly?
@bill How many parts are in the SW1998 assembly?