KDE applications starting slowly with remote X server

Beginner

Monday, June 28th 2004, 3:23am

KDE 3.2.3 on Debian Unstable

I have a setup with a powerful "application server" dedicated to running my applications. This machine has 2 x XP2200, 512MB and a filesystem spread accross 8 disks (6 scsi).

My workstation is a diskless PC running an X server against kdm on the application server, basically a thin client.

Everything is running fine, except:
Starting most (any?) KDE applications takes 5 seconds or more. This time is certainly not spend waiting for hardware resources.

'strace -T konsole' reveals that something tries to connect to /tmp/.X11-unix/X0 six times during startup, waiting one second between each attempt. Finally the application sees reason and connects to the remote X server making konsole appear. The attempts to connect to the non-existant local X server seem to be a terrible waste of time.

<snip>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000062>
socket(PF_FILE, SOCK_STREAM, 0) = 4 <0.000087>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000050>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000061>
connect(4, {sa_family=AF_FILE, path="/tmp/.X11-unix/X0"}, 19) = -1 ENOENT (No such file or directory) <0.000104>
close(4) = 0 <0.000061>
rt_sigprocmask(SIG_BLOCK, [CHLD], [],

= 0 <0.000074>
rt_sigaction(SIGCHLD, NULL, {SIG_DFL},

= 0 <0.000071>
rt_sigprocmask(SIG_SETMASK, [], NULL,

= 0 <0.000061>
nanosleep({1, 0}, {1, 0}) = 0 <1.002515>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000064>
socket(PF_FILE, SOCK_STREAM, 0) = 4 <0.000087>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000053>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000050>
connect(4, {sa_family=AF_FILE, path="/tmp/.X11-unix/X0"}, 19) = -1 ENOENT (No such file or directory) <0.000106>
close(4) = 0 <0.000059>
rt_sigprocmask(SIG_BLOCK, [CHLD], [],

= 0 <0.000068>
rt_sigaction(SIGCHLD, NULL, {SIG_DFL},

= 0 <0.000070>
rt_sigprocmask(SIG_SETMASK, [], NULL,

= 0 <0.000062>
nanosleep({1, 0}, {1, 0}) = 0 <1.002543>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000009>
socket(PF_FILE, SOCK_STREAM, 0) = 4 <0.000030>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000007>
uname({sys="Linux", node="lyn", ...}) = 0 <0.000007>
connect(4, {sa_family=AF_FILE, path="/tmp/.X11-unix/X0"}, 19) = -1 ENOENT (No such file or directory) <0.000033>
close(4) = 0 <0.000016>
rt_sigprocmask(SIG_BLOCK, [CHLD], [],

= 0 <0.000008>
rt_sigaction(SIGCHLD, NULL, {SIG_DFL},

= 0 <0.000009>
rt_sigprocmask(SIG_SETMASK, [], NULL,

= 0 <0.000008>
nanosleep({1, 0}, {1, 0}) = 0 <1.002374>
</snip>

What is causing this silly behaviour? -and how do I get rid of it?

Best Regards,

Michael A.

Go to the top of the page

cmbofh

Intermediate

Posts: 539

2

Monday, June 28th 2004, 5:25pm

Re: KDE applications starting slowly with remote X server

Quoted

Original von mandersen

KDE 3.2.3 on Debian Unstable
[...]
Everything is running fine, except:
Starting most (any?) KDE applications takes 5 seconds or more. This time is certainly not spend waiting for hardware resources.

'strace -T konsole' reveals that something tries to connect to /tmp/.X11-unix/X0 six times during startup, waiting one second between each attempt. Finally the application sees reason and connects to the remote X server making konsole appear. The attempts to connect to the non-existant local X server seem to be a terrible waste of time.

I think I can confirm what you're seeing. In my case the machine is running a kdm so I don't get the "no such file or directory" message but it fails one step later:
[code:1]Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified
[/code:1]
(This message comes up only once, not six times as in your case (*).)

It should not try to connect to the local X server on that machine because I'm starting that app from a ssh session with X11 forwarding.

The app comes up anyway after some time (that may well be the normal startup time of a KDE app over my slow LAN (10 MBit)) and on the correct X server (the one I'm sitting in front of ;-)).

No idea how to solve it, though. I'm also on KDE 3.2.3 on Debian unstable. Maybe that's a packaging problem? Can anyone with a different distro confirm this behaviour?

---------

(*) This is true if I've run another KDE app recently. The first KDE app
to start up causes more output:
[code:1]QPixmap: Cannot create a QPixmap when no GUI is being used
QPixmap: Cannot create a QPixmap when no GUI is being used
Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified

QPixmap: Cannot create a QPixmap when no GUI is being used
QPixmap: Cannot create a QPixmap when no GUI is being used
kbuildsycoca running...[/code:1]
This seems to be the startup of needed services. In this case the time needed is several seconds longer.

Go to the top of the page

cmbofh

Intermediate

Posts: 539

3

Monday, June 28th 2004, 6:07pm

Re: KDE applications starting slowly with remote X server

Quoted

Original von cmbofh

No idea how to solve it, though. I'm also on KDE 3.2.3 on Debian unstable. Maybe that's a packaging problem? Can anyone with a different distro confirm this behaviour?

I tested this myself by connecting to an older Gentoo box I still have around (KDE: 3.2 BRANCH >= 20040204) and there the problem does not occur.

It would still be good if someone with KDE 3.2.3 on a distro other than Debian unstable could try it out.

Go to the top of the page

mandersen

Beginner

Posts: 2

4

Tuesday, June 29th 2004, 3:14pm

Re: KDE applications starting slowly with remote X server

Quoted

Original von cmbofh

I tested this myself by connecting to an older Gentoo box I still have around (KDE: 3.2 BRANCH >= 20040204) and there the problem does not occur.

It would still be good if someone with KDE 3.2.3 on a distro other than Debian unstable could try it out.

I seem to recall that the server I previously had installed (also Debian Unstable) did not have this problem. Back then the KDE version would probably have been an early 3.2.

I think I will try to raise the problem as a Debian bug.

Best Regards,

Michael A.

Go to the top of the page

KDE-Forum.org