I've been disappointed with the overall performance and stability of GrapheneOS on my Pixel 7 Pro after switching from LineageOS.
Mull/Firefox was especially problematic. Loading JS-heavy pages was sluggish, toggling full-screen videos would often break in various ways, and every 10-15 minutes of browsing would result in the whole phone becoming unresponsive for a few seconds and the Mull process crashing. Often other background processes would be killed as well during these crashes. It felt almost like out-of-memory events.
Another app with obvious performance degradation was OsmAnd. Rendering map tiles was even slower than on my old Pixel 5. The System Settings app also often stuttered.
All of these problems resolved after I turned off Secure App Spawning (and restarted my phone). Using my Pixel 7 Pro is so much smoother and a more pleasant experience.
My question is why did this have such a big impact, especially for things like rendering speed? My understanding is that the setting should only affect process spawning. Is it possible the Android schedular is treating forked processes differently? Maybe some kind of CPU priority issue?
