File Gets larger and larger for no reason

I’m running Mac OS Monterey 12.6.3 with the latest version of Audacity (3.24)

I was having significant performance issues and noticed that my file size was over 6GB. I usually have 4 mono tracks for a roughly 1 hour podcast and it runs between 2-2.5GB in many cases. One of my cohosts has had files run 8-10+ GB for one hour. What are we doing wrong here?

I was having significant lag in performance (maybe because the file was too big), so manually copied each track into a new file, saved that as an MP3, then recombined the four mono tracks (which were each ~179MB files) into a new blank project and hit save. The project was 3.21GB after me doing nothing.

Performance had improved tremendously, but as I’m now editing further, the file continues to grow. I deleted 10 seconds of audio, the file grew to 3.22GB. Deleted a little more, and it grew to 3.33GB. I’ve only edited one additional minute of a 75 minute file, and the file is almost 50MB BIGGER. How does deleting audio to make the entire file shorter make it larger? I saved the file thinking perhaps it was just caching weird or something. Nope, the file is just bigger. I made the entire thing shorter, removed several labels, and it’s a bigger file.

What am I doing wrong here?

Yes. If I create an empty project on WIndows, the saved .aup3 file will be 20KB. If I open that project and Generate 1 hour mono track, I now have a 683GB file. Effect > Amplify > .01 will result in a 1.367MB file. A second Effect > Amplify > .01 results in a 2.051GB file. (Note, this is in addition to the temporary -shm and -wal files).

Why is my file tripling in size (even more if you count the temporary files)? Because Audacity retains all of the accumulated UNDO information should you decide you made some erroneous operation(s). Edit > Undo will undo these operations but won’t release the space - at least not until you make another change (for Redo).

To release all of this “undo” space, you simply need to save (Ctrl+S) AND close the file (Ctrl+W). Audacity will release all of the extra space (including my -shm and -wal) files. Note that just saving the file is NOT sufficient. In my case, my .aup3 file went from 2.051GB back down to 683GB after the close.

There is an unrelated issue that can occur when copying selected portions of a large track to a different Audacity .aup3 workspace. In this case ALL of the audio information from the original track may be copied to the new project. Workarounds exist for this issue and an integrated solution for the behavior is expected in 3.3.0