Recently I started to observe this very confusing and annoying, not to say worrying behaviour when having Firefox open and then launching Chromium:
For around 30 seconds, Firefox' child processes would consume all available CPU resources, causing websites to stop render (already displayed page freezes, new pages show a white page with grey spinning circle) while the overall window is still responsive (menus, page scrolling, switching tabs, even internal pages like about:config or about:preferences work...). Chromium itself does not show any symptoms. Terminating Chromium again immediately, while Firefox is spinning, does not stop the behaviour any faster.
The same happens with my regular Firefox profile, a brand new, untouched Firefox profile without any add-ons etc., Firefox started in safe mode with add-ons disabled, and Firefox started in private mode. Similar for Chromium, I can launch it with my regular profile, in incognito mode or with a temporary profile, always generating the same results.
There is nothing odd happening when Chromium is running and I open Firefox.
When launching Firefox from a terminal, I sometimes get messages like these when I quit it while it is spinning (note the pipe error line mentioning some chromium ipc...):
ExceptionHandler::GenerateDump cloned child 32165 ExceptionHandler::SendContinueSignalToChild sent continue signal to child ExceptionHandler::WaitForContinueSignal waiting for continue signal... [Parent 26520, Gecko_IOThread] WARNING: pipe error (52): Connection reset by peer: file /build/firefox-8oo9jx/firefox-62.0+build2/ipc/chromium/src/chrome/common/ipc_channel_posix.cc, line 353 ExceptionHandler::GenerateDump cloned child 32274 ExceptionHandler::WaitForContinueSignal waiting for continue signal... ExceptionHandler::SendContinueSignalToChild sent continue signal to child
Strangely I could not reproduce that behaviour in a guest account or a newly created regular (admin) account.
Some system specs (updated):
- Ubuntu 16.04 (64 bit)
- Graphics hardware: Intel SkyLake integrated graphics (i5-6200U) + Nvidia GeForce 940M
Currently I have the
nvidia-410driver installed, but switched to the Intel prime profile. How can I further troubleshoot and fix this issue?
I made a performance profile with the Gecko Profiler Extension, installed to a clean fresh Firefox profile on my regular Ubuntu account. It can be found here: https://perfht.ml/2zpTWsh - The unresponsive time frame with 100% CPU usage should roughly correspond to the highlighted area on the Content Proc timelines, from roughly 18s - 56s.
I created a Mozilla bug report for this issue: https://bugzilla.mozilla.org/show_bug.cgi?id=1504461
Important update: Apparently my bug report was a duplicate of https://bugzilla.mozilla.org/show_bug.cgi?id=1495900, which points out
fontconfig as the culprit. Seems like starting Chromium is making a change in the font configuration somehow, which triggers a complete reload in Firefox. This fits the performance profiling report, and also aligns with how former updates to font packages have triggered the same kind of freeze.
Any ideas how I can make the three (Firefox, Chromium, fontconfig) behave nicely along each other?