On Saturday 02 June 2012 14:06:48 Mike Gabriel wrote:

On Sa 02 Jun 2012 13:19:27 CEST Arnold Krille wrote:

...

On Friday 01 June 2012 08:32:40 Mike Gabriel wrote:

...

We developers can now confirm this. Ubuntu users reported this earlier, Debian user can now also experience such a sluggishness.

Reproduce on Debian:

• add squeeze-backports archive to your system
• install iceweasel (esr version)

This will drag in a libcairo from squeeze backports that is very probably the cause for making some applications very slow within X2Go sessions.

Libcairo is used in all GTK applications and is a layer between GTK and the rendering backend (X11, OpenGL, ...). With some recent version of libcairo the sluggishness got introduced...

Would it help to mask/block the libcairo from squeeze-backports? Or test with a newer version from wheezy? Maybe I can squeeze that in next week... When blocking from squeeze-backports you block out latest iceweasel/icedove and many other libcairo/gtk based packages as well.

iceweasel and icedove are coming not coming from squeeze-backports here I think. (My co-admin added some repositories so we get all the freshest (and untranslated:) ice*-apps.)

For wheezy, an installation without the slow libcairo is rather unpossible.

So the problem is any version newer than that in debian stable?

Have a nice weekend,

Arnold

On Wed, 2012-06-06 at 10:10 -0400, John A. Sullivan III wrote:

On Fri, 2012-06-01 at 08:32 +0200, Mike Gabriel wrote:

...

Hi,

just for the record and to let people know about current work focus...

People (esp. John) have reported occurrences of a very sluggish
behaviour of various applications when run in X2Go sessions.

We developers can now confirm this. Ubuntu users reported this
earlier, Debian user can now also experience such a sluggishness.

Reproduce on Debian:

• add squeeze-backports archive to your system
• install iceweasel (esr version)

This will drag in a libcairo from squeeze backports that is very
probably the cause for making some applications very slow within X2Go
sessions.

Libcairo is used in all GTK applications and is a layer between GTK
and the rendering backend (X11, OpenGL, ...). With some recent version
of libcairo the sluggishness got introduced...

@John: so it is not Nagle, I guess...

Compare: launch gnome-terminal (uses libcairo) on such a system and
xterm (uses direct X11 rendering). Now create some output on standard
out and then scroll back the shell history...

Alex has become aware of this on Linux Day Berlin and he has put it on
his list with high priority to find a solution/workaround for that.

<snip> Hmm . . . as I think about it, although I eagerly await this fix, I believe we are looking at two separate issues. We are still running 3.0.1 series on our production servers and clients because of this issue (and some others). However, I personally run the latest client from heuler. I have the problem on both the latest x2goserver and the old 3.0.1-5 x2goserver. It appears to be a client and not a server issue and appeared with the move to libssh.

The delay is not inconsequential. We are not talking about a sese of sluggishness with a 250ms delay. We are talking about a 2 to 5 full second delay for the final keystrokes or screens to appear. Everything else until the final bit is lightning fast even on WAN links - John <snip> I happened to have an old 3.0.1-7 plugin sitting around and tried that. I observed some of the same naglish behavior so it may not be the x2goclient. Unless someone else is experiencing this, I need to investigate our environment more fully before sending the devs on a fruitless search - John