Circular Linking of Models and Campus Buildings

I am working on a document for my office which details best practices for large project management. The section I am working on now is about splitting large files into various parts whether based on discipline, wings of the building, interior vs. exterior shell models, etc.

Here's my question: I've been advising people in my office to avoid linking models in a circular pattern. In other words linking one model into another that is then linked into the first. My assumption is that this leads to poorer performance because Revit has to analyze two layers deep to understand the elements that are in in the native environment even if they won't be shown. Is that a correct assumption?

Similar idea for worksets that are turned off (interiors turned off in campus file, but still present!)?

I've not observed poorer performance as a result. Many times "Circular linking" is necessary to be productive, especially when we've separated inter-related parts of the project that need to be seen together for context. Revit won't open a second file that is linked into the current open file unless you agree to unload the link first, that's the essence of the dialog message that appears.

Do you feel it's the same when you are looking at a workset that is turned off? I've always felt that linking a shell into a campus file is better than linking an entire building in and just turning off the interior elements as a workset.

I generally only use a campus file to establish shared coordinates that all building files can use and to generate site related views/documents. Otherwise all documentation is organized in building files themselves. Revit works best conceptually (reality is why we end up splitting them) when all the related pieces and parts are in the same file, the highest level of integration.

If a single building is two files, for example shell and interior, then they both need to be linked into each other for context while working in one or the other. They don't always need to be visible but there are certainly times when it is helpful. As you said I'd certainly link the shell model into the campus (site) file. However, the interior model does not necessarily need to be linked into the campus file at all. The campus site model can be linked into the shell model for context if necessary and that's where the circular relationship appears. In practice I'd seldom have them both open at the same time and Revit would want me to unload the other if I tried to open them both in the same session anyway.

Closing worksets improves performance to some degree but since the elements exist and elements we can see can have relationships with those that are part of a workset that is closed Revit can't ignore them entirely. We'll still experience some performance hit when we do something that interacts with and element in a closed workset. The most obvious or perceptible benefit is just that Revit does not spend anytime generating the elements assigned to a closed workset in any view we open. Collectively we experience a bit of an improvement though just how noticeable it is will vary greatly from one project to another.

Assigning linked files to worksets is a workaround to resolve the way Revit deals with unloading and reloading links. Unloading is a global transaction affecting all users while reloading is a local transaction affecting only the user committing the reload. Opening and closing a workset is always a local transaction affecting only the person doing the closing or opening. This means assigning a link to a workset and only closing or opening that workset means we don't have to chase the link around with Manage Links > Reload. In a perfect world it wouldn't be necessary to do it because unloading a link should effectively accomplish the same thing as closing its workset, without the extra organizational steps.

Not sure I've really answered your questions...

We also only use campus files for site related documents and presentation documents also. Perspectives and whatnot.

I was only wondering if circular linking would cause slowdowns, but it appears not. We have some circular links in much that same way that you have been using them for coordination.

We are working on a 330,000 sf condo building surrounded by a ring of sixteen 5000 sf custom homes. All of these in a campus file with all of their interior information and other baggage in addition to quite a large topography and myriad tress (site is another link in itself) makes for a pretty slow model. We are working on slightly outdated machines, but so far haven't had major slowdowns on any project under 150 mb.

I've been trying to manage file sizes, compressing, and purging, and now I am restructuring the file into smaller chunks (shells and interiors) to make this workable all the way through CD's. I would've liked to have the file structure conversation when we started, but alas, management isn't as well trained as one might hope and they didn't involve me until later.

I've also found a number of references on these forums about cleaning out the warnings dialogue box so I'm going to start managing that as well, and hopefully we won't have too many problems.

You've been very helpful, thanks!