413859 - Slow textareas

Status: RESOLVED WORKSFORME

(Core :: DOM: Editor, defect)

Description

[Christian Höltje]

This is with FF3b2 on Mac OS X 10.5.

What Happens:
  If I go to a page with a textarea and start typing, the textarea is very slow.  This is a big problem when using the arrow keys to navigate (they use auto-repeat) because you just keep going.

What I Expect:
  Feedback should be fast or instantaneous.

Additional Notes:
  The URL bar is also a little laggy, so <input type=text> may also have the same problem.

Ciao!

Comment 1

[Boris Zbarsky [:bzbarsky]]

1)  Probably an editor issue, not a form controls issue.
2)  There's a number of bugs on this already.  Unless there is a _particular_
    textarea that's particularly slow (in which case it should be profiled, and
    then we'll see), this is a duplicate of one of the existing "editor
    performance sucks" bugs.

Comment 2

[Christian Höltje]

I didn't know the difference and when I searched, I didn't find anything that matched; I was probably using the wrong keywords.

Ciao!

Comment 3

[Christian Höltje]

Okay, I searched some and found the following bugs:

Bug 188318 – typing quickly causes high cpu usage
Bug 179593 – Typing performance in mail Compose body
Bug 182150 – Typing is unusably slow in mail main and composition windows (Mac OS Shared Menus)

The last one looks the most like what I'm complaining about but it is closed.

This might be related, but I cannot tell:
Bug 174823 – Re-enable async reflow and painting for text widgets

Oh, this one is good:
Bug 240933 – Plaintext editor should stop using <br> all over

But it still seems to be only part of the picture.  Nothing quite addresses the whole "The User's Experience is Sub-Optimal" part.

Ciao!

Comment 4

[a.barcomb]

I am observing the same problem which was originally reported.  I thought at first it might be related to It's All Text, but after disabling that and all other extensions the problem persists.  I have noted it from the last stable release, and through all the 3.5 betas and release candidates I have used.  Currently I am using: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.4; en-US; rv:1.9.1) Gecko/20090616 Firefox/3.5.

The problem is as follows:  When Firefox is first started, there is no problem, but after about a day it starts to get slow.  After Firefox has been running for about three days, typing in a textarea is so painful that I reboot.  After 1 day it's a 9600 modem--text appears with a visible delay, but after 3 days it's like a 2400 baud modem--I can type the entire text and then sit back and watch it appear.  The length of time that a tab has been open does not appear to affect anything; if a tab is closed and later opened again, the problem persists.  

I agree with the previous poster that the other bugs suggested do not appear to capture the problem.  CPU usage does not appear to be affected (as in bug 188318); my load average is currently 0.17, CPU usage 5.9%.  Firefox has now been running 4:22:10.  Memory use does not appear to be out of control.

This cannot be observed for all websites (perhaps it is the site's JavaScript?). Here are some example sites:
  Always: https://twitter.com
  Sometimes: http://www.guardian.co.uk/commentisfree/ (pick any thread)
  Never: bugzilla

Comment 5

[a.barcomb]

Still being observed with Twitter in Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.4; en-US; rv:1.9.1.1) Gecko/20090715 Firefox/3.5.1.

Comment 6

[a.barcomb]

Note: it is also impossible to switch to another tab while waiting for the text to be entered, after the text has already been typed.

Comment 7

[Christian Höltje]

I haven't noticed any real issues on this for a while. So this can probably be closed.

Comment 8

[Wayne Mery (:wsmwk)]

Thanks for the update.