How Does Ventura Update Faster?
Watch Activity Monitor during those phases, and you’ll see that the download phase has significant CPU use by com.apple.StreamingUnzipService, which as the subsystem name suggests is decompressing the download as it arrives on your Mac. Understanding what’s going on during preparation requires browsing the log, where there’s evidence of further small downloads, some decompression and preparation of updates, and installation.
Although the progress indicators and times shown during updates in Big Sur and Monterey seem to have been broadly accurate, for Ventura they’re wild overestimates. That’s because the total time expected remains 30 minutes, and progress isn’t measured in terms of real time, but using staging points in the process. Hopefully as this matures in Ventura, the progress bar will be linked back to real time.
Previously:
I wonder why they’re using Zip, after having previously pushed more efficient algorithms.