158782 - Mozilla exhibits a lag in displaying typed text

Status: VERIFIED FIXED

(Core :: DOM: Editor, defect, P3)

Description

[derek fong]

From Bugzilla Helper:
User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en-US; rv:1.1b) Gecko/20020722
BuildID:    2002072203

Mozilla 1.1b doesn't display characters as they are typed.  Rather, there is a
lag between the time a character is typed vs. when it actually shows up on
screen.  This is especially evident the faster you type.

Reproducible: Always
Steps to Reproduce:
Type in the URL bar or in any form text box.


Actual Results:  There is a lag between typing and actually seeing the
characters typed.

Expected Results:  There should be no noticeable lag.

Comment 1

[WD]

*** This bug has been marked as a duplicate of 83205 ***

Comment 2

[kinmoz]

I don't think this is a dup of 83205, but rather a side effect of fixing bug 141900.

Comment 3

[Vidar Haarr (not reading bugmail)]

Confirmed on WinXP trunk build 2002072104.

Comment 4

[Matthew T (active 1999-2002)]

*** Bug 160920 has been marked as a duplicate of this bug. ***

Comment 5

[Matthew T (active 1999-2002)]

Reproduced in this `Additional Comments:' field right now, build 2002080503, Mac
OS 9.2.2, iMac DV 450 MHz, 64 MB RAM. --> All/All based on dup.

The delay is directly proportional to the amount of text following the caret
until the end of the paragraph.
-   If there's no text following the caret, the display keeps up with my typing
    fairly comfortably (though it would probably have trouble with extremely
    fast typists).
-   If there's one line of text (80 characters) to the right, and I type a
    group of words at constant speed, the caret display keeps up, but the text
    is never displayed (thanks to the fix for bug 141900) until I finish.
-   If there are three lines of text (240 characters) between the caret and the
    end of the paragraph, typing slows down so much that Mozilla forgets large
    chunks of the characters I typed and it comes out in a complete jumble.
    (Sample from my previous attempt at typing this: `Mozll culyforgetcers I
    typed and it comes out in a complete jumble.') In this case, even the caret
    movement can't keep up, and the text display never gets a chance.

Comment 6

[WD]

*** Bug 171693 has been marked as a duplicate of this bug. ***

Comment 7

[Benjamin Smedberg]

*** Bug 165032 has been marked as a duplicate of this bug. ***

Comment 8

[Benjamin Smedberg]

*** Bug 163367 has been marked as a duplicate of this bug. ***

Comment 9

[Benjamin Smedberg]

Bug 163367 was about backspacing in the URL bar, instead of typing forward, but
the essentials are the same.

Is the event model flexible enough that we could synchronously paint the
character that was typed as we process the keyboard event, rather than
invalidating the area and waiting for painting to occur later?  (Or clear the
area in the case of a backspace)?  If we are invalidating/waiting, this may be
affected by event starvation.

Comment 10

[WD]

As a note: when Mozilla is exhibiting this lag, my CPU usage goes up to nearly
100% while I'm typing but then returns to normal when I stop.   (I'm not sure if
this was obvious from the comments so far)

I notice it mainly when composing an email message or reply to somebody.
I'm not sure if we have more than one bug at hand here....

Comment 11

[WD]

*** Bug 172139 has been marked as a duplicate of this bug. ***

Comment 12

[kinmoz]

This bug has been temporarily fixed on the TRUNK with the checkin of attachment
101640 [details] [diff] [review] from bug 141900 during the mozilla1.2beta milestone. It basically
disables the code which landed as part of attachment 87307 [details] [diff] [review] (async reflow and
painting for text widgets) until all issues blocking bug 174823 can be resolved.

Comment 13

[Jo Hermans]

*** Bug 174929 has been marked as a duplicate of this bug. ***

Comment 14

[Dimitrios]

verifying fixed on 2002101708, Win2K.

Comment 15

[kinmoz]

*** Bug 152356 has been marked as a duplicate of this bug. ***

Comment 16

[sujay]

verified per comments.

Comment 17

[Frank Klein]

Attachment: Graphic depiction of CPU utilization with Mozilla Mail and Notepad

Comment 18

[Frank Klein]

Aaargh... midair collisions.  

I am still seeing some minor lags when typing a message in the send window
(plain text).  It is not as bad as it was before this bug was fixed, but it is
still there.  

CPU utilization is unusually high when I am typing.  Each keypress causes a
spike in CPU utilization from 50-90%, with some going to 100% (which causes a
lag).  I typed a string into Mozilla mail and into Notepad to compare the CPU
utilization, and the results were striking.  I sent the wrong image; the first
one has only Mozilla Mail.  There is almost no detectable change in CPU
utilization when typing into Notepad and letting it sit idle; in Mozilla, it is
very obvious.  In the image, you can plainly see when typing began-- in about
the center of the graph.  I'll send the proper attachment in a minute.  Using
2002101708/WinXP SP1/ 900 MHz AMD Duron/ 320 mb RAM.
 

Comment 19

[Frank Klein]

Attachment: CPU utilization while typing the listed string into Notepad and Mozilla

Comment 20

[adi]

I am now noticing delayed typing with the new version of sea monkey. It happens in email and at the address bar.