desktop-packages team mailing list archive

[Rolf Leggewie <277069@xxxxxxxxxxxxxxxxxx>]

Hardy has seen the end of its life and is no longer receiving any
updates. Marking the Hardy task for this ticket as "Won't Fix".

** Changed in: libxcb (Ubuntu Hardy)
       Status: In Progress => Won't Fix

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https://bugs.launchpad.net/bugs/277069

Title:
  Slow performance with remote X applications (java, firefox/xul, etc.)

Status in libxcb:
  Fix Released
Status in “ia32-libs” package in Ubuntu:
  Fix Released
Status in “libx11” package in Ubuntu:
  Invalid
Status in “libxcb” package in Ubuntu:
  Fix Released
Status in “ia32-libs” source package in Hardy:
  Won't Fix
Status in “libx11” source package in Hardy:
  Invalid
Status in “libxcb” source package in Hardy:
  Won't Fix
Status in “ia32-libs” source package in Intrepid:
  Invalid
Status in “libx11” source package in Intrepid:
  Invalid
Status in “libxcb” source package in Intrepid:
  Invalid
Status in “ia32-libs” source package in Jaunty:
  Won't Fix
Status in “libx11” source package in Jaunty:
  Invalid
Status in “libxcb” source package in Jaunty:
  Won't Fix
Status in “ia32-libs” source package in Karmic:
  Fix Released
Status in “libx11” source package in Karmic:
  Invalid
Status in “libxcb” source package in Karmic:
  Fix Released
Status in Debian GNU/Linux:
  Fix Released
Status in “libx11” package in Fedora:
  Fix Released
Status in Suse Linux:
  New

Bug description:
  With xcb every write (in _XFlush) is followed by a read (_XEventsQueued) which
  is the cause of the very poor performance. The read usually returns EAGAIN
  because there is nothing to be read, but it is a severe performace hit anyhow. 
  And why _XEvenetsQueued/read is being called when select/poll has previously
  returned indicating only a single file descriptor was ready is anybody's guess.

  [Original Report]
  I've submitted this bug as https://bugs.freedesktop.org/show_bug.cgi?id=17868 as well. Though the problem may not be in ia32-libs -package, it contains the /usr/lib32/libX11.so.6.2.0 library that appears to be somehow relevant to the problem at hand.

  Some Java applications, such as the trial version in
  http://www.typingmaster.com/, run unusably slow when used over a
  remote X connection.

  I'm using Ubuntu Hardy 8.04.1 with LTSP5, Linux kernel
  2.6.24-19-server, with 32-bit firefox and 32-bit Java-plugin.  The
  relevant package versions are here:

  firefox32 2.0.0.17
  sun-java32 1.6.0.5
  sun-java6-jre 6-06-0ubuntu1
  ia32-libs 2.2ubuntu11

  The issue does not appear to be Java-version related (it exists in 1.5
  and 1.6 versions).  I have not tested the very latest Java-versions
  though.  The reason I'm reporting this as a possible XCB-related issue
  is that one can workaround the problem by using an X11-library that
  does not link to XCB.

  In current Ubuntu version (Hardy), /usr/lib32/libX11.so.6.2.0 library
  links to /usr/lib32/libxcb-xlib.so.0 and /usr/lib32/libxcb.so.1
  libraries, XCB version is 1.1.  In previous Ubuntu version (Gutsy) the
  X11-library does not do this. When the new library shared object
  replaced with the old one, the problem disappears, and Java
  applications that had problems run fine.

  There may be some other differences between the X11-libraries, but
  using XCB as an underlying implementation seems to be a major change,
  or is it?  All other applications do not appear to have these
  problems, Java applications appear to be the sole source of these
  problems.

  I'm adding two attachments that show tshark-dump of network traffic in
  both cases, perhaps it helps to analyze the issue.  What happens there
  is one keypress on typingmaster Java-version, on Hardy/XCB case it
  takes half a minute to process one keypress and switch a screen, on
  Gutsy/no-XCB case it takes maybe a second.

  Juha

  [lspci]
  00:00.0 Host bridge [0600]: VIA Technologies, Inc. VT8623 [Apollo CLE266] [1106:3123]
      	Subsystem: VIA Technologies, Inc. Unknown device [1106:0000]
  01:00.0 VGA compatible controller [0300]: VIA Technologies, Inc. VT8623 [Apollo CLE266] integrated CastleRock graphics [1106:3122] (rev 03) (prog-if 00 [VGA controller])
      	Subsystem: VIA Technologies, Inc. VT8623 [Apollo CLE266] integrated CastleRock graphics [1106:3122]

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