1363391 - Regression: 100% CPU usage on Facebook tab when chat window is opened

Status: RESOLVED DUPLICATE of bug 1363176

(Core :: Networking, defect)

Description

[:gerard-majax]

Attachment: profile.fbmessenger.json

STR:
 1. Open https://www.facebook.com
 2. Click on a contact to start a discussion

Expected:
 Normal system load

Actual:
 After a few second, CPU usage spikes at 100%.

Closing the chat window takes CPU down. Killing the high-cpu process from htop kills the Facebook tab.

This is a 100% repro regression since a few days, and at least nightly https://hg.mozilla.org/mozilla-central/rev/b21b974d60d3075ae24f6fb1bae75d0f122f28fc

Comment 1

[:gerard-majax]

That's reproduced with mozregression. Starting good point of march 1st, today is exposing the behavior.

Comment 2

[Pascal Chevrel:pascalc]

I can confirm the bug with Mozilla/5.0 (X11; Linux x86_64; rv:55.0) Gecko/20100101 Firefox/55.0 ID:20170509100208 CSet: b21b974d60d3075ae24f6fb1bae75d0f122f28fc

Comment 3

[:gerard-majax]

10:44.22 INFO: Running mozilla-central build built on 2017-05-04 16:02:16.134000, revision 6d4525b5
10:57.53 INFO: Launching /tmp/tmpzL7LJD/firefox/firefox
10:57.54 INFO: application_buildid: 20170504154001
10:57.54 INFO: application_changeset: 6d4525b5aaa834ea4db8d8eab8087d86e34cf57a
10:57.54 INFO: application_name: Firefox
10:57.54 INFO: application_repository: https://hg.mozilla.org/mozilla-central
10:57.54 INFO: application_version: 55.0a1
Was this inbound build good, bad, or broken? (type 'good', 'bad', 'skip', 'retry' or 'exit' and press Enter): bad
11:33.19 INFO: Narrowed inbound regression window from [33b92d9c, 0b255199] (3 revisions) to [33b92d9c, 6d4525b5] (2 revisions) (~1 steps left)
11:33.19 INFO: Oh noes, no (more) inbound revisions :(
11:33.19 INFO: Last good revision: 33b92d9c40562dab3d7b602368c75619f1d793f7
11:33.19 INFO: First bad revision: 6d4525b5aaa834ea4db8d8eab8087d86e34cf57a
11:33.19 INFO: Pushlog:
https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=33b92d9c40562dab3d7b602368c75619f1d793f7&tochange=6d4525b5aaa834ea4db8d8eab8087d86e34cf57a

Comment 4

[:gerard-majax]

:bbouvier noticed on IRC that: https://hg.mozilla.org/mozilla-central/rev/d3b488ac423b#l2.1283 HSTS including messenger.com

Comment 5

[:gerard-majax]

Moving component, seems to be related to networking.

Comment 6

[Patrick McManus [:mcmanus]]

might be a dup.. probly related to tfo given that its fb specific

Comment 7

[Dragana Damjanovic [:dragana]]

Can you please make a http log.

https://developer.mozilla.org/en-US/docs/Mozilla/Debugging/HTTP_logging

you can use:

set MOZ_LOG=timestamp,rotate:200,nsHttp:5,nsSocketTransport:5

Thanks!!!!

Comment 8

[:gerard-majax]

Why do you need this log ? You don't reproduce the issue ?

Comment 9

[:gerard-majax]

See above, comment 8

Comment 10

[Dragana Damjanovic [:dragana]]

I do not have a facebook account. I will make 2 to start a conversation.

Comment 11

[:gerard-majax]

I have 60+MB logs, I'll share that.

Comment 12

[:gerard-majax]

(In reply to Patrick McManus [:mcmanus] from comment #6)
> might be a dup.. probly related to tfo given that its fb specific

I tested following :dragana's instruction and disabled network.tcp.tcp_fastopen_enable, reloaded the Facebook tab, and the issue would still get reproduced.

Comment 13

[Dragana Damjanovic [:dragana]]

Form log I have not seen a lot of activities on socket thread. At the begining yes, but later it is sleeping for a long time and between going to sleep and waiking up there is not much nsHttp logging as well, almost no logging. I am not sure this is necko.

Comment 14

[Timvde]

I noticed this too a few days ago, and made a performance profile: https://perfht.ml/2qCymi7. When I noticed the problem wasn't fixed after updating, I wanted to file and found this bug. Looks like a lot of time is spent in mozInlineSpellResume::Run()? Which would explain why a chat window causes the bug.

The performance profile is not in a clean Firefox profile, though. I can reproduce it if needed.

Comment 15

[Daniel Holbert [:dholbert]]

Comment 14 sounds like bug 1363176. Not sure if this whole bug is a dupe of bug 1363176 though.

Comment 16

[(no longer active)]

This is a dupe of bug 1363176.  I put the STR in that bug.