Performance with large files is sluggish & frequently enters the "Not Responding" state. This wastes my time & causes frustration. Files with this behavior include those with many linked or embedded images or complex vector graphics such as expanded brush strokes. However, I cannot find an explanation for this slowness. During these periods, my total RAM usage does not go above 40% & CPU usage does not go above 20%. GPU usage spikes to 100% occasionally but quickly returns to near 0% so this does not seem to be the cause. Opening & saving files takes a very long time & I have a NVMe SSD. Photoshop seems to handle large complex files like a champ & uses more RAM. I could be wrong, but it seems like hardware is being ineffectively utilized somewhere in AI. My best guess as to the cause is that AI is frequently reading data from the scratch disk or file instead of loading it into RAM & reading from that or that it is not parallelized to use multiple CPU threads. I don't perceive a difference between compressing or not compressing the file (in the AI save options). Hopefully this can be improved or I can learn what the bottleneck is.