I’m working on a big project with lots of detail and have multiple OmniGraffle drawings open with different sets of canvases. Specifically, there are three separate files, with 4 to 12 canvases each, and some of those canvases have a lot of objects.
I’ve noticed that when all three are open, some things get VERY slow. For example, if I clone a canvas (or even create a new one), it takes maybe 10 seconds to get control back. Meanwhile, the canvas thumbnails get scrambled on all the open windows. It seems like OG is recalculating the layout of ALL the documents any time I change the canvases in any one of them.
This seems like a really pointless thing – obviously, adding a canvas in one document shouldn’t have any bearing on another. But it’s not just a harmless quirk, it ends up taking a really long time just by having a large document open, even though my computer itself is still perfectly responsive with other applications. I can run other heavy software at the same time (CAD, or video playback) without any noticeable impact on performance.
I’ve noticed that it can even get laggy while editing, like taking around a full second to select an object in the drawing after clicking on it. Closing one of the other large documents helps this, making the delay imperceptible again. Why? Shouldn’t each document be in an independent thread? As long as I have available RAM and CPU cores, why is OG getting so bogged down just by having other detailed drawings open – in a different window, even on a separate desktop?
Just for reference, OG 7.20 on MacOS Big Sur 11.6.5 on a 2018 Mac Mini (6-core 3GHz i5, 32GB RAM, flash storage.) Activity Monitor shows that the system is coasting most of the time, with plenty of unused memory.