JIT Behavior

[networkException]

It looks like disabling JIT only disables turbofan since a more recent version, perhaps we want to revert that change just as the Vanadium folks: GrapheneOS/Vanadium@09797bd

[PF4Public]

Vanadium is GPL, we cannot just take their patches.

[networkException]

its just a commit revert

[luke-jr]

I've implemented a new setting to turn off JIT, but my patch is against mainline Chromium and I don't really have the time to sort out whether they will apply cleanly here or rebase them even if they don't... But if someone wants to do so, I'm fine with the BSD-3-clause license.

settings-jsjit.patch

page_info-jsjit.patch

page_info-jsopti.patch

[PF4Public]

@luke-jr What was the reasoning behind toggling kBug364820109AlreadyWorkedAroundPref?

[luke-jr]

Originally, Chromium had this option for JAVASCRIPT_JIT, but replaced it with JAVASCRIPT_OPTIMIZE when Webasm was released (details elided). When that happened, they cleared all the previous _JIT site overrides since users no longer had control over them.

The workaround pref tells Chromium not to clear the overrides "again".

In practice, everyone today probably already has it set - it's only useful if upgrading from an older version where the user has overrides already. (Which was the case when I first created these patches)

[luke-jr]

Actually, since this is changing the setting default rather than assigning to it, it's entirely possible that I don't have it set still, and toggling it back would lose my own overrides😬

I'm not sure if others' similar patches (GrapheneOS has something like this too) would have the same methodology and thereby impact users' profiles