1360160 - Firefox hang when clicking an item in https://store.docker.com/search

Status: RESOLVED WORKSFORME

(Core :: Disability Access APIs, defect, P3)

Description

[kodmivi]

This bug was filed from MDN. Firefox is hanging, and manually crashing using crashfirefox64.exe produces this crash report: https://crash-stats.mozilla.com/report/index/622b6e18-cc02-4686-b722-9d53d1170427

Steps to reproduce
1. Open https://store.docker.com/search?operating_system=windows&q=&source=verified&type=image
2. Click on 'nanoserver' item.

Comment 1

[kodmivi]

More details:
- When hanging, Firefox consumes 100% of CPU core.
- The stack-trace of the hanging thread contains 'mozilla::a11y::NotificationController::CoalesceMutationEvents()' function call.

Comment 2

[:Gijs (he/him)]

Based on the stack mentioned in comment #1, this looks like an a11y bug to me.

Comment 3

[Marco Zehe (:MarcoZ)]

Alex, have you seen this before?

Comment 4

[alexander :surkov (:asurkov)]

Nope. CoalesceMutationEvents is a known bottle neck though. I'm curious if Firefox 48, which has bug 1261425, is any better.

In general I think we should try to go towards to pruning events in subtree (like bug 1301829).

Comment 5

[:Gijs (he/him)]

(In reply to alexander :surkov from comment #4)
> Nope. CoalesceMutationEvents is a known bottle neck though. I'm curious if
> Firefox 48, which has bug 1261425, is any better.
> 
> In general I think we should try to go towards to pruning events in subtree
> (like bug 1301829).

The crash/hang is from 53.

Comment 6

[Alice0775 White]

I attempt finding regression window with Windows10 64bit Nightly 32bit with e10s disabled + a11y activated w/Japanese IME ATOK2016.

#1 Regression window(Hang at step 1):
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=850159471c686be76390a2ee8dae12afbac7cc32&tochange=f38aaa49ed11b2e20bced1334e44e203b29e1040

Regressed by: Bug 1296420

#2 Regression window(Hang at Step 2)
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=ef23bf8110953349a23ba2e344c20643b392eda0&tochange=387d3acae9e99bdc140a65fd367ecbaa6238f3a3

Regressed (partially progressed?) by: Bug 1270916


@Michael Li and @:tbsaunde,
These patches cause the hang. Please look this?

Comment 7

[Alice0775 White]

(In reply to :Gijs from comment #5)
> (In reply to alexander :surkov from comment #4)
> > Nope. CoalesceMutationEvents is a known bottle neck though. I'm curious if
> > Firefox 48, which has bug 1261425, is any better.
> > 
> > In general I think we should try to go towards to pruning events in subtree
> > (like bug 1301829).
> 
> The crash/hang is from 53.

I can reproduce the hang on 52esr w/ e10s disabled + a11y activated. The combination is default for ATOK2016 IME user.

Comment 8

[Marco Zehe (:MarcoZ)]

Michael Li was an intern and is currently no longer with us, and Tbsaunde is on PTO. Alex, see comment #6 for the regression windows.

Comment 9

[alexander :surkov (:asurkov)]

(In reply to Alice0775 White from comment #6)
> I attempt finding regression window with Windows10 64bit Nightly 32bit with
> e10s disabled + a11y activated w/Japanese IME ATOK2016.
> 
> #1 Regression window(Hang at step 1):
> https://hg.mozilla.org/integration/mozilla-inbound/
> pushloghtml?fromchange=850159471c686be76390a2ee8dae12afbac7cc32&tochange=f38a
> aa49ed11b2e20bced1334e44e203b29e1040
> 
> Regressed by: Bug 1296420

this bug is surprising with me, cannot think how it may make the event coalescence worse.

> #2 Regression window(Hang at Step 2)
> https://hg.mozilla.org/integration/mozilla-inbound/
> pushloghtml?fromchange=ef23bf8110953349a23ba2e344c20643b392eda0&tochange=387d
> 3acae9e99bdc140a65fd367ecbaa6238f3a3
> 
> Regressed (partially progressed?) by: Bug 1270916

ok, that's what I concerned about in 1270916 comment #c73, when switched from EventTree coalescence (introduced in bug 1261425).

I'm also curious if single process Firefox is same bad as e10s one.

Comment 10

[Sylvestre Ledru [:Sylvestre]]

Moving to p3 because no activity for at least 1 year(s).
See https://github.com/mozilla/bug-handling/blob/master/policy/triage-bugzilla.md#how-do-you-triage for more information

Comment 11

[James Teh [:Jamie]]

I can't reproduce this. Either the page changed or there was an improvement in Firefox. It's impossible to say which. Either way, this isn't actionable now.