Dorico is very slow on a big project


I’m working on a big Dorico Project that is very slow : it takes about 20 sec. to add an instrument in a percussion kit. Even the note input is quite slow. I turned off the playback (NotePerformer) and nothing changes. I looked at my activity monitor and the CPU usage never goes above 30%.

I’m wondering if I could send it privately to someone who could check how it works on their computer.



It would be helpful if you would add your computer information and Dorico version.


Dorico 4.0.31
iMac 27 2019
MacOS 12.3.1
i5 3,0 gHz 6-cores (this one I think : iMac (27-inch Retina Early 2019) Benchmarks - Geekbench Browser)
RAM : 24 Go

Operations like adding players and instruments (even adding an instrument to an existing percussion kit) will indeed be slow in very large projects. The fundamental reason for this is that each operation that changes the list of instruments in a flow has to recalculate the layouts that are currently shown (in windows or tabs within those windows, even if they are not currently visible on screen because the window is behind the active window, or tabs are in the tab bar but not currently the active tab) from scratch. When you open a project, the majority of the time taken after starting the operation and the project window appearing is taken up with calculating the layout, rather than reading the file itself. It’s this process, the recalculation of the layout, that is performed when you add or remove instruments, so just as a larger, more complex project takes longer to open than a smaller one, so too does adding or removing instruments.

We do have plans to improve the performance of these kinds of operations in future versions, though it’s not a simple thing to achieve.

As for general editing slowness, even a small edit can have a large knock-on effect on the layout and formatting of the whole layout, and while Dorico does its best to minimise the amount of recalculation required, there are certainly some pathological cases that are disproportionately expensive.

If you want us to look into the specific performance characteristics of your project, you can attach it here or send it to me via a direct message, but please include specific information about the kinds of edits you find slow, and exactly where you are making those edits (layout, instrument, flow, bar).