Is anyone using the new iMac Pro to run SketchUp Pro 2020?

Given that I’m a dedicated Mac person, I’m debating the wisdom of buying a new iMac Pro to run SketchUp 2020.
My goal is to get some, or any improvement to my current dismal and appalling Layout performance, which is a total and complete productivity bottleneck in an otherwise quiet joyful SketchUp experience. (And yes, I have followed the Forum Layout comments for years and have tried or implemented ALL of the suggested workflow optimizations …) Like a lot of you, I’m still frustrated with Layout.
So, is anyone out there already using and experiencing the newer iMac Pro (which can feature my preferred configuration as below) to run SketchUp Pro?
3.2GHz 8-core Intel Xeon W processor, Turbo Boost up to 4.2GHz (base Spec.).
32GB 2666MHz DDR4 ECC memory (base Spec.).
Radeon Pro Vega 64 with 16GB of HBM2 memory (upgrade from base).
2TB SSD storage (upgrade from base).
If so, I’m particularly interested in how Layout behaves and performs with that new Radeon Pro Vega 64, 16 GB graphics processor?
I’m limping along with my old iMac 27" Core i7 4.0 5K, (Late 2015), which has an AMD Radeon R9 M395X graphics processor with only 4 GB of GDDR5 memory.
Focusing on Layout’s performance and speed in particular, is an upgrade to the iMac Pro from my existing iMac spec’s. perceptible? Would you advise that the upgrade to an iMac Pro (and the big bucks!) is “worth it” for the Layout performance improvement?
Any informed opinions would be most appreciated!

I use a late 2012 iMac and I don’t experience the issues you do. Could be a question of model size perhaps, if you handle big ones.

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I have just noticed something about LO that I hadn’t before.

If I go into LO and open a SU file from it, doing something like adding text in LO slows to a crawl. But if I don’t open the SU file, everything works at normal speed. That suggests there is some kind of interactivity going on even when the SU file is not being changed. Makes no real sense.

However, if this is anything to do with the issues you have found, an answer might be to close the SU file once you stop needing to have it open.

2020 has a lock feature. Would be interesting to see if locking models that you don’t need to modify would help with performance.

I’m due to do a screen share with an affected user in a little while. I’ll try that.

I presume by “lock feature” you mean this?

Screenshot 2020-03-17 at 17.40.53

This is the drawing I was working on earlier where inputting text was soooooooooooo slow. But re-opening it and re-opening the SU file from within it, the problem no longer exists. So my earlier assumption looks wrong. Maybe it’s another of those Gremlin things that software technicians just can’t chase down?

Layout seems to be affected as soon as you insert a Model of any size. Even a simple Box slows it down. It’s got to be something to do with the viewport, as when you zoom to an area where there is no viewport showing, it speeds back up.

I’d be interested in an answer to this as well.

I’m thinking of the same iMac Pro as you but with 64GB RAM, mainly because on my current iMac, when I upgraded to 40GB, I did notice a jump in Layout Perfomance.


This is an interesting discussion. I am on a Windoze platform and I can tell how Layout will run when I start it. If the trays populate slowly, Layout will not co-operate. a restart is required. If the trays pop up all is good to go. I do not think this is a specific computer issue but something is loaded that is conflicting with the Layout operation.
Last night I had two instances of SU running and one instance of Layout running with no issues with speed or performance.

I tried the lock model idea on my screen share, and it didn’t solve the problem. Also found out that when the problem starts it will continue to be wrong until you quit LayOut.

The problem being that you make changes and don’t seem them on the page, but you do seem them in the page thumbnail image. Resizing the window, or doing any amount of zoom, will make the changes appear on the page.

We have a related issue that was Magic Mouse specific, and for my screen share case I had them change to a regular USB mouse for a while, to see if that made things any better. I haven’t had a report back yet to know if that helped.

I did notice that the user I was screen sharing with did a lot of zooming in and out, and that could be a factor. I’m going to do more testing where I also zoom around a lot.

Beamer2, what input devices do you use?

on a mac…

inside LO are many the same frameworks that create the SU application…

when LO ‘opens’ a model it basically runs an almost complete version of SU internally…

that’s why it slows down…


OK but does that explain why the same LO file works at normal speed for some of the time and slow speed at other times (when little has been done to it apart from closing and re-opening)?

The problem I get is mostly to do with the speed that text appears on screen compared to the speed at which I type. Normally, as when I type something like this, it is in sync, but sometimes in LO it lags way behind.

My iMac Pro (10 core 64gb ram) handles SketchUp and LayOut smoothly…even big files and rendering. LayOut has some performance slowdown when switching to Vector rendering mode as it does on any machine. I’ll try and do a benchmark test between Macbook Pro and iMac Pro to see if there is a difference with a ‘heavy’ LayOut file and report back.


Thanks Mike,
Yes, 64 GB of Ram certainly couldn’t hurt (other than maybe the pocketbook!).

Thanks Eric,
Your report is encouraging … so maybe there is hope, if I just spend enough money!

Thanks Simon,
I’ve experienced this same Layout speed variable, slow sometimes, and even slower other times. Text entry often seems to be the worst. I haven’t been able to apply enough pattern recognition to figure out what is different from one session to another. If the answer is logical (we have to hope), then you are right that there has to be SOME setting, action, operation, view, command (or command sequence), or tool that is causing a reduction in speed. If we could just figure it out, then we could avoid it! Wouldn’t that be nice! Trimble?

Hey John,
It sounds like you have an answer here … Can you elaborate a little bit? I would really like to understand exactly what you are saying!
This prompts lots of questions:
Does this mean that LO is basically running itself AND SU simultaneously and is therefore slower? Does it follow then that the bigger the SU file, the slower LO runs?
If so, has anyone experimented to find the ratio of this relationship?
If true, does this suggest particular SU/LO workflow methodologies?
On and on …

Hi Colin,
I’m using a 3DConnexion 3 button SpaceMouse with SU 2018.
I haven’t made the jump to SU 2020 yet, but soon.

My iMac Pro doesn’t buy me very much speed as I don’t think SketchUp takes advantage of parallel processing. One recent animation output took over 6 hours to process. Here is the model … thousands of vectors need processing. I don’t see why SketchUp doesn’t see any parallel processing opportunities.

My model is 595 MB. It is a walk thru model of a model railroad museum. Within this model are about 60 models of buildings that will be on the layout.

Hey Russ,
Thanks for your reply - I gather you are running SketchUp Pro on an iMac Pro. Can you tell me the spec’s on your unit, specifically what graphics processor you have?
If you read my initial post of March 16, you will see my inquiry was focused on Layout performance (most people don’t have any serious problems with SketchUp performance or speed, it’s all about how dog slow Layout can be!). This is why having an older quad core processor with a higher clock speed (like my 4.0 GHz) is perhaps preferable to newer 8 core and up processors which tend to top out at 3.6 GHz.
And yes, we all know that SketchUp can only utilize one “thread” or processor core, so multiple core processors don’t benefit SketchUp speed (but they will still benefit other activities such as rendering programs).
My question continues to be: Is the souped up graphics processor in you iMac Pro (please specify yours) giving you better speed performance and response in LAYOUT? As I am contemplating the purchase of an iMac Pro (with a maxed out graphics processor), I want you impressions/experience running Layout (preferably with big files).
Please post your opinions on this!

Hey Russ,
I responded to your post with a question on May 3, but I didn’t see any response …
Again, I’m seriously considering upgrading my iMac 27" 5K Late 2015 i7 4.0 Ghz, 32 GB Ram, AMD Radeon R9 M395X 4 GB video, machine to an iMac Pro w/ similar ram and with a maxed out 16 GB video card.
Based on your experience, does LayOut specifically, perform better with all this extra video memory, and if so, how much better? Let me know …
Thanks, Beamer

Hi @Beamer2

I’m also looking at going for the new iMac Pro soon and would be interested in this answer.

One thing that made a huge difference on my current Retina iMac when I bought that was upgrading the RAM. When I took delivery of it, it only had 8GB RAM. I’d always planned to upgrade the RAM myself rather than pay Apple prices. I upgraded to 40GB and it made a huge difference to Layout. Using 8GB, it would have been quicker to hand draw everything rather than use Layout. While it is still jumpy and a pain to use, the 40GB did make a massive difference. It’s is useable now. But, Layout STILL needs to be majorly sorted. If I insert PDFs into Layout and then zoom in on them, I get the beachball of death for ages, and we’re only talking 200kb PDFs. In my opinion, Layout needs to be rewritten.

Therefore, I’m thinking as well as the top GPU, I’ll probably go for 64GB RAM.