1497072 - Firefox sometimes won't throw suggestions while writing into adress bar on a slow I/O USB device

Status: RESOLVED INCOMPLETE

(Firefox :: Address Bar, defect)

Description

[Vaidas.BoQsc]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:62.0) Gecko/20100101 Firefox/62.0

Steps to reproduce:

Running Ubuntu 18.04 on an USB3 16GB flash
I started up Firefox and began typing, but suggestions never shown up.
I finished typing and hit enter. Google popped out immediately with the results.


Actual results:

Most of the times I tried - suggestions never popped. Only sometimes for unknow reason and not when it was expected for suggestions to show up.


Expected results:

Autocompletion/suggestions should have happen. 
But it seems to never happen.
Maybe that's due unusually slow speed of USB3 device. 
So, please optimize it. It shouldn't be like that.

Comment 1

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

It's possibly due to the device, as you suspected. What may help here is getting a performance profile through https://perf-html.io/ so we can check where we spend the most time.

Comment 2

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

Could you please also do some testing of I/O throughput for that device? so we can compare. There should be a few tools around to measure read/write throughput.

Comment 3

[Vaidas.BoQsc]

Attachment: Screenshot from 2018-10-10 17-50-22.png

Comment 4

[Vaidas.BoQsc]

Performance profile: https://perfht.ml/2C7mIRw

Comment 5

[Vaidas.BoQsc]

Keep in mind that while making Performance profle, I was unable to get any suggestions even if I waited for 1 min.
Also I'm running on Persistent Ubuntu 18.04 that was made using: https://help.ubuntu.com/community/mkusb

Considering remaking/reinstalling Ubuntu just to make sure that bug persist. That will be done probably tomorrow.

Comment 6

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

Hm, from the profile it looks like the events loop is completely stuck, I doubt the event reached the urlbar *at all*. Thus I'm not sure I'm the right person to investigate this, I was hoping to see some storage access.
I'm not sure what's the right component for this.

Mike, any idea?

Comment 7

[Vaidas.BoQsc]

I'm getting unsure of what actually caused suggestions to not appear, it seems that after Ubuntu operating system restart, the suggestions appears instantly whenever I write anything into address bar.

I tried to make the computer go into sleep mode, but that didn't cause this suggestions bug.
So far, suggestions responds very well. 
I'll try to reproduce the bug later if I find out how.

Comment 8

[Mike Conley (:mconley) (:⚙️)]

(In reply to Marco Bonardo [::mak] from comment #6)
> Hm, from the profile it looks like the events loop is completely stuck, I
> doubt the event reached the urlbar *at all*.

I'm looking at https://perfht.ml/2C7mIRw, and the event loop looks free and clear (the poll() libc function that dominates the main thread in the parent process is us polling for OS events).

I do see evidence of UnifiedComplete handling the key presses in the profile.

I suspect we're dealing with a graphics, XUL, or GTK widget issue where Firefox _thought_ the popup was being displayed, but it wasn't actually visible to you.

Comment 9

[Darkspirit]

(Just in case they are related in some way.)

Comment 10

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

Unfortunately the system setup is not trivial to reproduce, comment 8 may be right about it being an invisible popup, due to a graphical problem.