Bug 22007 – Scrolling speed

• Component: Layout and Rendering
• Status: RESOLVED WORKSFORME

[Dmitry]

WebKit with Qt has EXTREMLY slow speed of scrolling on some sites. For example, at gmail.com with about 100 letters per page. Scrolling speed is like on P-II with 32 Mb of RAM.

My PC is Sempron-2800, GeForce 7800GS, 2Gb DDR-II. Video drivers are installed from repository of KUbuntu Gutsy.

Scrolling in Opera works 10 times faster on such sites.

Please, fix it.

[Adam Treat]

This is not descriptive enough and is not experienced by me nor have I heard of such reports from others who use QtWebKit daily.

[Dmitry]

Opera works fine, Firefox works fine, Konqueror works fine. Webkit doesn't. Don't know why it is not descriptive enough, the scrolling speed is simply slow. Very slow. I can grab video.

[joe]

Same problem

[Adam Treat]

What versions of QtWebKit are you guys using?  Is this with recent Tip Of Tree or one of the released versions with Qt.  And if one of the released versions with Qt please do tell is this with QtWebKit released with Qt4.4?

[Dmitry]

Any version is affected. I used all webkit versions from Qt 4.4 to 4.4.3, and many svn revisions (from 30000 or something to 40618).

We are developing the internet browser for internal purposes based on webkit and the one of the worst things with it is a scrolling speed. Now my system is Debian Lenny on Athlon X2 5600 and it is still works very slow. If you want I can grab video with the latest svn trunk and other browsers, you should see THIS :)

[Adam Treat]

You've mentioned this on gmail.com.  Are there any other sites where you see this?  If so, please list them.

[Adam Treat]

*** Bug 24183 has been marked as a duplicate of this bug. ***

[Adam Treat]

I'd also be interested in a video if you were serious.

[Dmitry]

Yes, some other sites are scrolled very slow too. I'll try to grab some videos tommorrow.

[joe]

Many sites slow either very slow, or incredibly jerky for me. http://www.mysticwicks.com being one in particular. 

I'm using SuSE 11.1, QT4.5,  Xorg 7.4, Intel video driver, and the KDE 4.3
(svn) Desktop.

I'd try to do a video as well, though I'm not sure how.

[joe]

(In reply to comment #10)
> Many sites slow either very slow, or incredibly jerky for me.
> http://www.mysticwicks.com being one in particular. 
> 
> I'm using SuSE 11.1, QT4.5,  Xorg 7.4, Intel video driver, and the KDE 4.3
> (svn) Desktop.
> 
> I'd try to do a video as well, though I'm not sure how.
> 

Sorry, I meant many sites SCROLL either very slow..or..

Typo. 

[Adam Treat]

What depth is your x-server configured too?  Question for both of you guys.  Note: you can use xdpyinfo and xwininfo to tell.

[joe]

screen #0:
  print screen:    no
  dimensions:    1280x1024 pixels (365x292 millimeters)
  resolution:    89x89 dots per inch
  depths (7):    24, 1, 4, 8, 15, 16, 32
  root window id:    0x87
  depth of root window:    24 planes
  number of colormaps:    minimum 1, maximum 1
  default colormap:    0x20
  default number of colormap cells:    256
  preallocated pixels:    black 0, white 16777215
  options:    backing-store NO, save-unders NO
  largest cursor:    64x64
  current input event mask:    0xfac031
    KeyPressMask             EnterWindowMask          LeaveWindowMask
    KeymapStateMask          ExposureMask             StructureNotifyMask
    SubstructureNotifyMask   SubstructureRedirectMask FocusChangeMask
    PropertyChangeMask       ColormapChangeMask
  number of visuals:    2
  default visual id:  0x21
  visual:
    visual id:    0x21
    class:    TrueColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits
  visual:
    visual id:    0x22
    class:    DirectColor
    depth:    24 planes
    available colormap entries:    256 per subfield
    red, green, blue masks:    0xff0000, 0xff00, 0xff
    significant bits in color specification:    8 bits


---

That is mine.

[Dmitry]

name of display:    :0.0
version number:    11.0
vendor string:    The X.Org Foundation
vendor release number:    10402000
X.Org version: 1.4.2
maximum request size:  16777212 bytes
motion buffer size:  256
bitmap unit, bit order, padding:    32, LSBFirst, 32
image byte order:    LSBFirst
number of supported pixmap formats:    7
supported pixmap formats:
    depth 1, bits_per_pixel 1, scanline_pad 32
    depth 4, bits_per_pixel 8, scanline_pad 32
    depth 8, bits_per_pixel 8, scanline_pad 32
    depth 15, bits_per_pixel 16, scanline_pad 32
    depth 16, bits_per_pixel 16, scanline_pad 32
    depth 24, bits_per_pixel 32, scanline_pad 32
    depth 32, bits_per_pixel 32, scanline_pad 32
keycode range:    minimum 8, maximum 255
focus:  window 0x1800021, revert to PointerRoot
number of extensions:    35
    BIG-REQUESTS
    Composite
    DAMAGE
    DOUBLE-BUFFER
    DPMS
    Extended-Visual-Information
    GLX
    MIT-SCREEN-SAVER
    MIT-SHM
    MIT-SUNDRY-NONSTANDARD
    NV-CONTROL
    NV-GLX
    RANDR
    RECORD
    RENDER
    SECURITY
    SHAPE
    SYNC
    TOG-CUP
    X-Resource
    XAccessControlExtension
    XC-APPGROUP
    XC-MISC
    XFIXES
    XFree86-Bigfont
    XFree86-DGA
    XFree86-Misc
    XFree86-VidModeExtension
    XINERAMA
    XINERAMA
    XInputExtension
    XKEYBOARD
    XTEST
    XVideo
    XVideo-MotionCompensation
default screen number:    0
number of screens:    1

screen #0:
  dimensions:    1280x1024 pixels (342x271 millimeters)
  resolution:    95x96 dots per inch
  depths (7):    24, 1, 4, 8, 15, 16, 32
  root window id:    0x1a6
  depth of root window:    24 planes
  number of colormaps:    minimum 1, maximum 1
  default colormap:    0x20
  default number of colormap cells:    256
  preallocated pixels:    black 0, white 16777215
  options:    backing-store NO, save-unders NO
  largest cursor:    64x64
  current input event mask:    0xfa4031
    KeyPressMask             EnterWindowMask          LeaveWindowMask
    KeymapStateMask          StructureNotifyMask      SubstructureNotifyMask
    SubstructureRedirectMask FocusChangeMask          PropertyChangeMask
    ColormapChangeMask
  number of visuals:    120                                                                           

[Tor Arne Vestbø]

*** Bug 29397 has been marked as a duplicate of this bug. ***

[Benjamin Poulain]

I have tried gmail and http://www.mysticwicks.com on Linux and both do fine when scrolling (with webkit trunk, Qt and Webkit in debug mode).
I have also tried on the anomaly browser on the N900 and the scrolling speed is excellent (with Qt 4.6 and Webkit trunk, in release mode).

With which browser do you have the problem? Does QtLauncher have the problem as well?

Dmitry and joe, could you make a profile with valgrind and attach it to this bug? (or maybe use oprofile if the time is spend outside Qt).

[Benjamin Poulain]

Adam, do you mind if I close this bug?
It has been here for a long time and it seems the reporter don't give any info to reproduce or a profile to see what the problem is.

[Adam Treat]

Closed for lack of information and inability to reproduce.