graphic dump on cluster

[Barry Smith]

  The X graphics in PETSc are intended for debugging and simple stuff;
this should be done on a laptop or workstation. Except in limited cases
I would not use it on a cluster.

   Barry


On Wed, 24 Jan 2007, Satish Balay wrote:

> Its hard to get this working properly on a cluster.
> 
> One way to do this is:
> 
> - ssh to each node [where the job will be run] so that
>   there exists a X11 tunnel from  all nodes
> - make sure all of them have the same ssh-x11 display. i.e
>   once you ssh - check with 'echo $DISPLAY'
> - now run the PETSc binary with this display value..
> 
> Satish
> 
> On Wed, 24 Jan 2007, Barry Smith wrote:
> 
> > 
> >   Note that the PETSc X model has ALL nodes connect to the X server (not
> > just where rank == 0). Thus all of them need 
> > 1) the correct display value (-display mymachine:0.0 is usually the best way to 
> >     provide it)
> > 2) permission to access the display (X permission stuff, read up on it) and
> > 3) a route to the X server (via TCP/IP).
> > 
> >   Barry
> > 
> > 
> > On Wed, 24 Jan 2007, Matthew Knepley wrote:
> > 
> > > On 1/24/07, js2615 at columbia.edu <js2615 at columbia.edu> wrote:
> > > > Hi Petsc experts,
> > > > 
> > > > I have a question about the graphic output using multiple
> > > > processors.  Suppose I am using X11 to ssh into the cluster, and
> > > > would like to view the graphical output at each iteration using
> > > > 
> > > > ierr = VecView(x,PETSC_VIEWER_DRAW_WORLD);CHKERRQ(ierr);
> > > > 
> > > > I got the following error message, turns out, when I use multiple
> > > > processors (not a problem using one processor though):
> > > > 
> > > > Unable to open display on localhost:10.0
> > > > .  Make sure your COMPUTE NODES are authorized to connect
> > > >     to this X server and either your DISPLAY variable
> > > >     is set or you use the -display name option
> > > 
> > >  The error message is exactly right. You either need to set the DISPLAY env
> > > var or give the -display option to PETSc. I think giving -Y to ssh forwards
> > > your
> > > Xconnection automatically (setting DISPLAY).
> > > 
> > >  Matt
> > > 
> > > 
> > 
> > 
> 
>