Deprecated documentation on Interactive jobs with graphical support

[laraPPr]

I noticed that this page in the documentation is deprecated, https://docs.hpc.ugent.be/Windows/running_interactive_jobs/#interactive-jobs-with-graphical-support. xclock is no longer a command that works on RHEL9 login nodes and nodes. A sutable altenative to quickly see if xforwarding works seems to be xterm.

I bumped into this no longer working when I was trying to use some application in the terminal that used LibGL. To check that those would work these commando's were handy (glxinfo and glxgears). I also ran into a bug or imcompatibility when ssh with xforwarding from a MacOS. I was trying to use an R package that relied on OpenGL. This was the error that I was hitting from MacOS, XQuartz/XQuartz#144 . Working from the Cluster Desktop seems than a more viable alternative.

Maybe we could expand the docs to have example of running an interative job from the Cluster Desktop in OOD. There is an example in the intro to hpc slides.

The example script also no longer works since the xmessage command is also no longer available on RHEL9. So that script will also need to be updated those are also managed in this repo, seee https://github.com/hpcugent/vsc_user_docs/blob/latex/intro-HPC/examples/Running-interactive-jobs/message.py. Possible alternatives for xmessage might be notify-send or zenity.

$ ./message.py 
/bin/sh: line 1: xmessage: command not found
  ---------------------------------------------------------
  < GET REAL! I am not a cow, I am a bunch of characters. > 
  --------------------------------------------------------- 
           \   ^__^ 
           \  (oo)\_______ 
              (__)\       )\/\ 
                   ||----w | 
                   ||     ||   

[backelj]

Note: these commands can be made available by installing the proper rpms. That is, the xorg-x11-apps in RHEL8 has been split into several packages on RHEL9, including xclock, xmessage and so on.

[stdweird]

@laraPPr open a jira to readd the packages on el9.

but the page should remain deprecated in favour of interactive desktops (or considered very very advanced usage). openGL over ssh probably is not doing what you think it does. i am curious to the usecase that needs this

[laraPPr]

The backend team is not gonna install those rpms I discussed it with them.

The problem I was hitting has something to do with Xquartz. So as you mentioned still give instructions on xforwarding but also add instructions on using the cluster desktop instead.

[laraPPr]

I was trying to run something with this package, https://cran.r-project.org/web/packages/rgl/index.html, but I could not even load it when using Xquartz. I already hit it by doing this.

options(rgl.debug=TRUE)
library(rgl)

[stdweird]

and it fails with interactive desktop? or rstdio server?

[laraPPr]

Only fails when I xforwarded from Mac with Xquartz. xforwarding from a vm on my worklaptop also worked. In rstudio server it also did not work because their is no DISPLAY I think, but I'm not sure. And in the cluster desktop it works.

[stdweird]

wrt rstudio, depends a bit what you need the opengl for. if it is to render images, we can probably make that work. for 3d visualisation, should have a look at the webgl support for rgl cfr https://cran.r-project.org/web/packages/rgl/vignettes/WebGL.html
anyway, open a jira for this if you need it

wrt the other cases, since the cluster desktop works, anything else should be considered deprecated/borken or very advanced usage

[laraPPr]

Agreed. Can you than update https://github.com/hpcugent/vsc_user_docs/blob/latex/intro-HPC/examples/Running-interactive-jobs/message.py and add instructions on running that on the Cluster Desktop?

To be clear this was a question for Godfried which I think is @Oa8choo2

[stdweird]

what is the jira for (not) installing xclock and friends?
wrt the script, i don't understand what it tries to achieve

[laraPPr]

No Jira but I talked to @wdpypere about and from that conversation I understood that we should not rely on xclock anymore and other x packages that are not supported by RHEL9 anymore.

The script just opens a simple window (see https://docs.hpc.ugent.be/Windows/running_interactive_jobs/#run-simple-example) where you can click yes or no.