Subject: Bug#586: X2Go session sometimes slows to a crawl

From: Stefan Radermacher <[email-masked]>
Date: Thu, 28 Aug 2014 14:23:39 +0200

Package: x2goserver
Version: 4.0.1.15

The client machine's OS: Gentoo Linux 64-bit
The client machine's version of X2GoClient: 4.0.2.1
Any relevant session settings in X2GoClient: KDE session
The server's OS: Gentoo Linux 64-bit
The server's version of the x2goserver package: 4.0.1.15
The server's version of the x2goserver-xsession package (included in
server package)
The server's version of the nx-libs package: 3.5.0.27

After a while of running, the session can slow down so that the
environment reacts very slowly, window changes come only after seconds,
and mouse clicks or keyboard presses only register after several
seconds, too. This happens even if there is no significant load on the
server machine.

On occasion, the session can actually recover from this state.

When the session is disconnected during such a slowdown, it terminates, too.

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From: Milan Knížek <[email-masked]>
Date: Thu, 28 Aug 2014 16:15:30 +0200

> On occasion, the session can actually recover from this state.

I experience the same behaviour for about 9 months now. Server is Arch
Linux x86_64 with recent x2go server. Client is on Windows XP. I do not
use clients on other OS's, hence cannot tell otherwise. Different
versions of neither client nor server seem to have any influence on the
behaviour.

Someone on the mailing list mentioned the reason could be antivirus
scanning the temporary files (i.e. locking them) on client. Since I use
a company PC, the antivirus cannot be prevented to ignore the x2go temp
files and I cannot tell if this really is the culprit.

However, since this affects also a Linux client in your case, I am more
inclined to an idea of too recent X libs - dependencies of apps - being
incompatible with the old x2go agent. (Both Arch and Gentoo are probably
ahead with upgraded packages compared to Debian).

Milan

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From: Milan Knížek <[email-masked]>
Date: Wed, 22 Oct 2014 11:11:31 +0200

> > On occasion, the session can actually recover from this state.

In PyHoca-GUI + Win 7 (I have used it for about one month now), it seems
to be more stable and the "slow-down" problem appears less often.

The following might be related: when I open any keepass window, the
window (db unlock, item display, whatever) is not drawn properly
initially - some parts are not drawn and instead the contents of another
window in the background is shown.
At the same moment all x2go windows freeze for about 30 seconds and then
all the apps (including keepass) continue to work normally. The
originally scattered contents of keepass window is eventually drawn
properly too.
Keepass is a Mono app.

Milan

---

From: Milan Knížek <[email-masked]>
Date: Wed, 22 Oct 2014 15:30:49 +0200

> originally scattered contents of keepass window is eventually drawn
Interestingly, the "freeze" period gets shorter down to cca 5 seconds,
when I used Xming+Putty X server (version 6.9.0.31).

Milan