1657651 - Loading issue when first launching Firefox 79

Status: RESOLVED WORKSFORME

(Core :: DOM: Service Workers, defect, P3)

Description

[Tom S [:evilpie]]

There many reports on reddit that when first starting Firefox the first page load has a very long delay.

• https://www.reddit.com/r/firefox/comments/i48kns/firefox_dont_load_pages_for_first_2030_sec_after/
• https://www.reddit.com/r/firefox/comments/i2ozip/new_session_delay/
• https://www.reddit.com/r/firefox/comments/i1vw8w/initial_click_on_bookmark_doesnt_work/
• https://www.reddit.com/r/firefox/comments/i1693k/bug_firefox_79_first_launch_wont_load_certain/
• https://www.reddit.com/r/firefox/comments/hkjao2/websites_wont_load_on_first_attempt_since_770/
• https://www.reddit.com/r/firefox/comments/hjr6da/some_websites_dont_load_at_first_try_new_firefox/

On user suggests disabling ServiceWorkers was working for them:
https://www.reddit.com/r/firefox/comments/i1693k/bug_firefox_79_first_launch_wont_load_certain/fzz6aq6/

Comment 1

[Mike Conley (:mconley) (:⚙️)]

At least some of this might be DoH or Necko startup? Any thoughts, valentin?

Comment 2

[Mike Conley (:mconley) (:⚙️)]

If it's ServiceWorkers, perhaps asuth would have thoughts on this too.

Comment 3

[Tom S [:evilpie]]

This post points to an incredible slow DNS response. So maybe two different issues.

Comment 4

[Valentin Gosu [:valentin] (he/him)]

(In reply to Mike Conley (:mconley) (:⚙️) from comment #1)

At least some of this might be DoH or Necko startup? Any thoughts, valentin?

Seems unlikely to be DoH. There's a 1.5 seconds timer in mode2 anyway, so it should actually block anything.
But without some logs/diagnostic info I can't say for sure if it's Necko related or not.

Comment 5

[:Gijs (he/him)]

bug 1656310 is assigned to :asuth, so clearing the stale needinfo here.

Comment 6

[:Gijs (he/him)]

Kim, this needed a severity; it's not really clear to me if this is all covered by bug 1656310 and should be duped, or if there's stuff left to investigate here. You marked this p2 from qf - is someone on the perf team available to investigate / dig into this? I'm guessing not...

Comment 7

[Kim Moir [:kmoir] ET]

No we don't have anyone from the perf team to investigate at this time.

Comment 8

[Tom S [:evilpie]]

This is still being reported: https://www.reddit.com/r/firefox/comments/jh5082/annoying_issues_in_firefox/

Comment 9

[Andrew Sutherland [:asuth] (he/him)]

In terms of long delay, ServiceWorkers depends on QuotaManager's initialization which can take some time, see the telemetry data at https://mzl.la/2TmoLbR

In terms of an infinite wait due to hung or aborted interception (but without triggering), some portion of the phenomenon was fixed by bug 1662925 and a different variant of the problem is being investigated in bug 1668743 with my direct work right now being on bug 1506892 to add instrumentation so we can figure out what's going on.

Comment 10

[BugBot [:suhaib / :marco/ :calixte]]

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Comment 11

[Olli Pettay [:smaug][[e-mail]]]

There have been plenty of fixes related to storage initialization etc. relatively recently.
Marking this WFM, but please file a new bug if you still see this happening.