glen1111@ Thanks for the issue.

Tested this issue on Ubuntu 17.10 and Windows 10 on the reported version 66.0.3359.139 and the latest Beta 67.0.3396.18 and unable to reproduce the issue.

1. Launched Chrome and logged into gmail account
2. Cannot observe any hang on Chrome when clicking on a mail thread, opening a chat, and scrolling through a mail.
Attached is the screen cast for reference.

Request you to retry the issue on a new chrome profile without any flags/extensions and update the thread with the observations.

Thanks..

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Thanks Susan for attempting to reproduce.

There is something there--we built three of these identical AMD
Threadripper machines MSI m/b with three different user setups and all
three showed this delay. One user went back to Firefox, I went to Chromium,
and one just reads gmail on his Mac instead. So I know there is a problem,
but it doesn't surprise me that it's only for some rare combination that we
triggered with this configuration.

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

glen1111@ Thanks for the update.

As this issue is reproduced on AMD Threadripper machine and this setup is not available at TE end to test further, adding 'TE-NeedsTriageFromMTV' label and requesting someone from MTV team to look into the issue and help in further triaging.

Thanks..

Hi glen1111@, it would be helpful if you could take a trace of the delays in action and attach it here. Instructions: https://www.chromium.org/developers/how-tos/submitting-a-performance-bug

Please use all categories in the left column and add just the "renderer.scheduler" category on the right side.

As per comment #6, issue seems to be reproducible on a AMD Threadripper machine and the system is not available at inhouse or MTV team. Hence, adding label TE-Hardware-Dependency.

Thanks...!!

Wasn't sure how to login into the bug system, so attaching it here.

I got a good one! < 10 seconds long and with a clear delay showing.

Actions:

- started tracing
- clicked on my Gmail tab
- clicked around for a few seconds on different things, no problem
- clicked to compose new email, started typing in my "To:" address
- HANG! (for about 3 seconds)

Unfortunately it seems email attachments don't work. If you could upload it to Google Drive or Dropbox or equivalent and share the link that would work too.

https://drive.google.com/file/d/1zF-PM_1j9chk94X8Z6gGI5Gk9wIL__x0/view?usp=sharing

Thanks for the trace. Attached here. Looks like an extremely long GC in the renderer. Over to MemoryAllocator team.

Deleted: trace_chrome.type.delay.json.gz 2.7 MB

trace_chrome.type.delay.json.gz 2.7 MB Download

Great, excellent that you folks are taking it seriously. Thanks for that!

It's frustrating to buy a 16-core (32-thread) machine and have your UI
thread stall for seconds in the middle of typing, while I imagine the other
31 threads are idle. Not cool!

Just to clarify and hone in your debug efforts--this occurs for me on this
AMD desktop machine ONLY in google-chrome, never in chromium-browser or
firefox.

One other useful question: does this happen only in Gmail or on any other pages?

Ah, great question. I have noticed it only in Gmail, but that is my
dominant activity in the browser.

It is possible it's Gmail specific.

Such long marking pauses will be gone once we land incremental marking.

Just my feedback: I don't know how many people are seeing this, but if it's
any substantial fraction then this should be P0. It's a total showstopper
for me using the product. Super annoying as it happens multiple times per
minute where my typing just stops going to the screen, or a click doesn't
work.