UI lag with small clips

[kentagent]

Hi everyone. I am having lag issues when using Audacity, currently version 3.7.1, though I don’t think it has changed from earlier versions. Specifically, the problem is with scrolling and zooming in the UI. It is related to the number of individual audio clips. That is, the lag appears, and increases, when there are many small clips. It also increases when I zoom out. If I zoom in far enough, I never have a problem no matter how big the project is. It is also not a problem with zooming out by itself or the length of audio since the experience is always smooth with fewer longer clips.

My conclusion so far is that there is more or less a linear relationship between the number of visible clips on the screen and once and this lagging problem. Is this a bug in general, or only happening on my system? Is anyone else experience the same?

I see this on two different computers. Both run Ubuntu, one 22.04 and the other 24.04. I use the AppImage version of Audacity. Both computers are reasonable powerful with Intel Core i7 and Xeon processors, respectively.

Thanks in advance!

[Trebor]

@kentagent

… the lag appears, and increases, when there are many small clips.

You say small, but small “smart clips” contain a copy of the entire track where they originated.
https://youtu.be/HpA138b-J9s?&t=79

@kentagent

Intel Core i7 and Xeon processors

They have up to 8 cores. Audacity is only using one of them.

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