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eric.bernier1
2010-04-14, 01:57 PM
Is there any documents describing or explaining if personnal computers working on big central files affect the overall project speed? I was wondering if there is a "weak link" effect in a project team of 30 people if there 10 of them using XP32 revit 2010 with 4 gig ram and all the other are working on Windows7 64 with 8 gig ram? Is ther eany chances that the slowest computers will drag down the others in any way?

I hope I'm clear enough, it is not easy to explain.,

Thanks!

Éric

cliff collins
2010-04-14, 02:03 PM
Yes--there is a published rule of thumb from Autodesk which states this:

Compacted Central File size x 20 = amount of memory required.

So-- 200 MB compacted Central file x 20 = 4 GB RAM required.

Thus, 32 bit machines, even with 3g switch enabled, will not be able to STC or Open
files of 200MB or larger in size, due to memory limitations with 32 bit OS.

The problem is, the 64 bit machines with lots of RAM will be able to Synch to Central, but then the 32 bit users will not be able to open or save the large files.

The trend is go to Win 7 64 bit, use 8 GB RAM minimum--12 -16 GB is even better, esp.
when working on large files with lots of linked models.

cheers........

wmullett
2010-04-14, 02:29 PM
You can still open using reduced worksets.

cdatechguy
2010-04-14, 03:11 PM
Even with worksets we have had people that were not able to save to central when using 32bit XP when everyone else is using 32bit Vista.

Having more than 6 people accessing the same central file will slow things down as well. So if you have 30 people accessing the same file... :shock:

twiceroadsfool
2010-04-14, 03:15 PM
To answer your actual question: No, it wont cause a "weakest link" issue in terms of physically slowing down the faster and better machines. The minor exception to this, is when the users get the "key symbol" while the slower machines are saving.

But what Cliff said is very true: if you HAVE weaker stations on the job, you have to build the model to the least common denominator, such that the weakest machine can handle it. Ive pushed on XP32 bit machines to a 200 MB model, but in that, even selective workset loading didnt help with the memory problems. Its pretty much a deal breaker.

wmullett
2010-04-14, 03:29 PM
We currently have a 250 meg project that also has linked in Revit structural and CAD MEP files and we do that on 32 bit, 4 gig machines. We use reduced worksets for most work that may still be needed on this project while it is under construction. Linked files are in worksets as well.

I will say that this file is still in Revit 8 because it was too big and too far along for us to convert when 2009 came out. We may not have been able to use this size file in 2009/2010 because they seem to need more memory.

cliff collins
2010-04-14, 03:39 PM
Yep.

2010 / 2011 software requires WAY more memory than older versions.

cheers

Steve_Stafford
2010-04-14, 04:58 PM
Revit performance documentation does mention a "weakest link" issue. The idea is that computers with poorer specifications and performance will affect the rest of the team when their PC's are engaged in crosstalk with the central file which is quite often regardless of using Sychronize with Central. Therefore it isn't a good idea to include weaker pc's as part of your group. How badly it will affect your actual project remains a bit harder to pin down.

ron.sanpedro
2010-04-14, 05:13 PM
The one area I know from experience will hurt is network speed. On a project with 15 users, the presence of just a few 100MB network connections would destabilize the whole team. We saw random crashes, even on brand new machines with gigabit networking. Once the entire team was running gigabit, stability for the whole team went way up. Note this was Windows XP x32, 4GB of RAM, Revit 2008 and a 150MB file. So even after getting everyone up to snuff on the networking, we still had issues as we pushed the limits on model size. But crashing went from an average of 1 or 2 people a day to maybe 1 a week, and that one was usually attributable to someone having too many other apps open, not working in limited loaded worksets, etc.

That said, I would argue that 30 active users is too much for any one model, no matter what kind of computer, server or network you are dealing with. If there is any way to split that up into 2 or 3 models it will likely help the whole process. And any project that honestly needs more than 10 concurrent users is likely to also require 64 bit and lots of ram. Revit 2011 will run on an older machine with only a few gigs of RAM and XP x32, but the projects will need to be small, and the teams likely small also. Like 2-3 concurrent users. Once the team is over 5 or 6, I would really be pushing for upgrades. The ROI is very much worth it.

Gordon