Open Bug 1157820 Opened 5 years ago Updated 2 months ago

[e10s] could the Debugger UI work for an ilooping content script before the 'Debug Script' button?


(DevTools :: Debugger, enhancement)

Not set


(firefox40 affected)

Tracking Status
firefox40 --- affected


(Reporter: luke, Unassigned)


(Blocks 1 open bug)


(This is more of a feature request b/c this doesn't work in non-e10s.)

It appears that, if you have an ilooping script, the only way to break in the debugger is to wait for the slow-script dialog and then click 'Debug Script'.  If the Debugger is already open, the UI is responsive (mmm, e10s), but clicking the Pause button has no effect.  Similarly, if you try to open the Debugger (before the slow script dialog), nothing is displayed until the slow-script dialog.

Fixing this (so that you could pause at any time) would be useful not just for debugging ilooping scripts (which in theory you can just wait out until the Slow Script dialog), but also in the case of big janks that aren't iloops, just a single turn of the event loop that takes a long time and you want to pause to see what's going on so you can step through it.
I personally would call it a bug when clicking pause isn't instant.

Setting dom.max_child_script_run_time = 1 is best you get at moment.
Can also try using profiler to determine where to place breakpoints.
Blocks: dte10s
tracking-e10s: --- → -
Product: Firefox → DevTools

Luke are these two related 1157816?

tracking-e10s: - → ---
Flags: needinfo?(luke)

IIUC, bug 1157816 was more of a simple bug report whereas I think this is a feature request. I just tried locally and it still seems to be the case that, while a script is ilooping or taking a long time, pressing 'pause' doesn't have any effect.

Flags: needinfo?(luke)
Type: defect → enhancement
You need to log in before you can comment on or make changes to this bug.