[chromium-dev] Intent to implement : Improve hang watching capabilities in chromium

[Olivier Li Shing Tat-Dupuis]

Contact email:

oliv...@google.com

What?

Implement a new class called HangWatcher that enables more robust and precise hang watching capabilities in all of chromium.

Why?

The current hang watching coverage is narrow and can lead to many non-actionable reports.

Design doc?

Here

CLs?

One for now : https://crrev.com/c/2008189

The plan to start is to first enable very simple hang reporting on the IO thread. This emulates what is currently achieved with ThreadWatcher. As the results come in the code will be improved and we will add filters to make sure all reports are actionable in the future.

Please let me know if you have any questions!

--

Olivier Li Shing Tat-Dupuis |

Software developer |

oliv...@google.com |

1-415-761-1995

[Ravi Raman]

Hello Olivier,

A couple of questions around these changes:

Is there a plan to enable the UI thread hang detection on browser process (discussed under ThreadWatcher section of your document) with the new hang watcher in the near future after fixing the limitations? 

Also, is there a release timeline you expect the other hang detection (like the GPU watchdog) to start using the new hang watcher?

Thanks,
Ravi

[Olivier Li Shing Tat-Dupuis]

Hello Ravi,

The plan is to start implementing the monitoring of the UI thread this week actually. That would bring experimentation with it in the next weeks. Before that some fixes are needed and are getting reviewed right now.

Regarding replacement of the existing methods: There is no set timeline yet for that. We are focusing on the browser process for now and will see in due time. The exception is ThreadWatcher/Startup hang detection which are actively being deprecated/deleted as we bring the HangWatcher online.

[Ravi Raman]

Hi Olivier,

Thanks for your reply. It is great to know that you will soon be implementing the UI Thread monitoring.

Quick follow up: Looks like the IO thread watcher is still disabled by default and hang detection on IO thread is still using the old watchdog (possibly awaiting the rest of the bug fixes you mention?). Will it be enabled by default soon? 

Thanks,
Ravi

[Olivier Li Shing Tat-Dupuis]

Hello again Ravi,

Thanks a lot for you interest :)

I'm currently working at less that 50% capacity so the progress is slow but it's going! I've created a tracking sheet for my work where I'm trying to make it clear when things will happen.