[Paraview] Newbie question about paraview's parallel visualization procedure

Wed Jul 11 03:41:48 EDT 2007

Thanks a lot for helping me with my frustrating condition.  The problem
with the invisible window being created whose title in the task bar is
"unable to open display" has gone, I compiled the sources again with
off-screen rendering enabled and start the paraview server with
off-screen rendering now.

Server end :
raashid at ender:~/src/cvs/paraview-unix-new/bin$ mpirun -np 2 ./pvserver --use-offscreen-rendering

Client End :
raashid at ged:~/src/cvs/paraview-unix-new/bin$ ./pvclient --server-host=10.101.11.72

The client gets connected to the server and works fine.

You suggested to check the check-box next to Composite and move the
slider all the way to the left (0 MBytes) and then try to visualize.
When I do this no matter how small the dataset is when I open it and
press the accept button a message is displayed saying "Server
connection has been dropped. ParaView client will be terminated"

The terminal output on client was :

raashid at ged:~/src/cvs/paraview-unix-new/bin$ ./pvclient --server-host=10.101.11.72
Connected to server
ErrorMessage
# Error or warning: There was a VTK Error in file: /home/raashid/src/cvs/ParaView/Servers/Common/vtkServerConnection.cxx (67)
 vtkServerConnection (0xc0ee1b8): Server Connection Closed!
ErrorMessage end

The terminal output on server was :

raashid at ender:~/src/cvs/paraview-unix-new/bin$ mpirun -np 2 ./pvserver --use-offscreen-rendering
Listen on port: 11111
Waiting for client...
Client connected.
-----------------------------------------------------------------------------
One of the processes started by mpirun has exited with a nonzero exit
code.  This typically indicates that the process finished in error.
If your process did not finish in error, be sure to include a "return
0" or "exit(0)" in your C code before exiting the application.

PID 6385 failed on node n0 (10.101.11.72) due to signal 11.
-----------------------------------------------------------------------------

Also I tried 3 different cases of composting for a dataset of 0.5
million (vtk-xml file type, try to draw glyph at each point)

Case 1. Composting is off 

Case 2. Composting is on and value is increased (to 10.0 MB)

Case 3. Composting in on and value is turned to 0.0 MB

In all cases I noticed one thing, on the lower left side of the
window, where the the running process is display, every time when the
message "MPIMoveData" is displayed the paraview crashes.

I dont know if this thing is useful, but I just wanted to let you know.  

On Mon, 09 Jul 2007 Moreland,Kenneth wrote :
>Raashid,
>
>
>
>As I stated in an email I sent out last week (attached), it looks like
>ParaView may have the parallel rendering turned off, in which case all
>the geometry will be pushed to the client (which in turn would cause the
>slow rendering and memory issues).
>
>
>
>Verify that parallel rendering is turned on.  Go to 3D View Properties.
>Make sure that the checkbox next to Composite is checked and move the
>slider all the way to the left (0 MBytes).  Also make sure that
>Subsample Rate is checked and move the slider to the right some.  Now
>when you do an interactive render (render while you are moving the
>mouse), the image should look blocky.  If it does not, parallel
>rendering is still off.  Check the DISPLAY parameters on the server to
>ensure that it can open rendering windows.
>
>
>
>-Ken
>
>
>
>________________________________
>
> From: paraview-bounces+kmorel=sandia.gov at paraview.org
>[mailto:paraview-bounces+kmorel=sandia.gov at paraview.org] On Behalf Of
>Raashid Baig
>Sent: Sunday, July 08, 2007 1:38 PM
>To: paraview at paraview.org
>Subject: [Paraview] Newbie question about paraview's parallel
>visualization procedure
>
>
>
>I am a newbie to parallel visualization and ParaView in general and I
>am some very basic problems with ParaView.
>
>I am using ParaView2.6.X and trying to do performance analysis with
>increasing dataset on ParaView as a part of an academic project. I
>want to see what are the gains in CPU & memory usage and time required
>to render a particular dataset when ParaView is runs in parallel. All
>machines have Intel Core Duo 2, 2GB DDR2 RAM, and 2GB swap, NVidia
>7series graphics cards and work on Debian/Ubuntu Linux.
>
>I have structured data-sets with point attributes in form of VTK-XML
>files (*.vts). When I run paraview in stand-alone mode on a single
>machine, I am able to draw glyph at each point of the data sets upto 1.5
>million grid points. But when I put the same VTK XML files on 3
>different computers (all have ParaView 2.6.X installed) and run ParaView
>through LAM/MPI in client-server mode where server is running on 2
>computers and the client is running on another computer, performance
>decreases drastically. Not only does the time taken to render final
>image, cpu and memory usage increase, I am only able to dram glyps till
>0.5 million grid points. After 0.5 million point the get an error (this
>particular error is for a dataset of 0.5 million) :
>
>on client :
>
>------------------------------------------------------------------------
>---------
>raashid at ged:~/src/cvs/paraview-unix-new/bin$ ./pvclient
>--server-host=10.101.11.72
>Connected to server
>ErrorMessage
># Error or warning: There was a VTK Error in file:
>/home/raashid/src/cvs/ParaView/Servers/Common/vtkProcessModule.cxx
>(1171)
>vtkProcessModule (0xc0c7530): Received exception from server:
>Insufficient memory exception.
>ErrorMessage end
>ErrorMessage
># Error or warning: There was a VTK Error in file:
>/home/raashid/src/cvs/ParaView/Servers/Common/vtkServerConnection.cxx
>(67)
>vtkServerConnection (0xc0ee1b8): Server Connection Closed!
>ErrorMessage end
>------------------------------------------------------------------------
>---------
>
>on master node of the server I get the following error message :
>
>raashid at ender:~/src/cvs/paraview-unix-new/bin$ mpirun -np 2 ./pvserver
>--use-offscreen-rendering
>Listen on port: 11111
>Waiting for client...
>Client connected.
>Process id: 0 >> ERROR: In
>/home/raashid/src/cvs/ParaView/VTK/Common/vtkDataArrayTemplate.txx, line
>95
>vtkFloatArray (0xad19b48): Unable to allocate 46593000 elements of size
>4 bytes.
>
>Process id: 0 >> ERROR: In
>/home/raashid/src/cvs/ParaView/Servers/Common/vtkProcessModule.cxx, line
>1187
>vtkProcessModule (0xa7f14c8): Exception: Insufficient memory exception.
>
>Am I using the wrong file type, if yes what should I use ?
>I have not changed any LOD parameters. Is there some threshold limit I
>am violating ?
>
>
>
>search
><http://adworks.rediff.com/cgi-bin/AdWorks/click.cgi/www.rediff.com/sign
>ature-home.htm/1050715198 at Middle5/1236533_1230311/1276266/1?PARTNER=3&OA
>S_QUERY=null%20target=new%20>
>
>
>
>Raashid,
>
>
>
>First, let me assure you that ParaView's parallel visualization and
>rendering are efficient and scalable.  We have been able to use ParaView
>to visualize 6 billion cell grids and have clocked rendering speeds of
>over 8 billion polygons per second (albeit with much larger clusters
>than you have set up).
>
>
>
>As far as your problems are concerned, I'm going to have to do a lot of
>guessing because I cannot replicate your problem and there are missing
>pieces of information.  Looking at your mpirun command, it appears that
>the DISPLAY variable is set to the same value on every process.  That
>is, all processes in the ParaView server are creating a remote (for
>them) X window on 10.101.11.71.  If that is the case, it is very, very
>bad.  Basically, that would mean that all of the rendering is being
>funneled into one computer.  Thus, instead of actually getting parallel
>rendering, you are getting serial rendering plus the added overhead of
>moving OpenGL primitives and images across the network plus the standard
>overhead of parallel rendering.  Note that because you are only using 3
>computers, I would not expect the parallel gains to be much higher than
>the natural overhead of the parallel algorithms.  If your computers are
>using a standard Ethernet connection, the relatively high latency and
>low bandwidth will further erode the parallel gains.
>
>
>
>The fact that your parallel job is crashing when you have a parallel job
>with a sizeable data set suggests that you might not be using parallel
>rendering at all.  You can shut off parallel rendering with the 3D view
>properties or ParaView will shut it off for you if the server cannot
>create the appropriate rendering windows.  When parallel rendering is
>shut off, ParaView does the only thing left: funnel all of the geometry
>to the client.
>
>
>
>Verify that you are actually doing parallel rendering.  Start by running
>in client/server mode (don't bother with parallel standalone: its
>usefulness is basically limited to debugging).  Go to 3D View
>Properties, verify that the checkbox next to "Composite" is checked and
>move the slider all the way to the left (0 MBytes).  If everything is
>working right, parallel rendering should now always be used.  The
>easiest way to verify that is to observe the subsampling, which only
>happens on interactive rendering when rendering in parallel.  Make sure
>that the checkbox next to "Subsample Rate" is checked and move the
>slider to the right to 4 Pixels or more.  Now when you rotate your 3D
>rendering, it should look pixilated.
>
>
>
>Offhand, I cannot think of another reason for your memory failures.  I
>just used the Wavelet source to create a 125,000,000 cell structured
>mesh on three nodes of our visualization cluster (each with 1 MB each),
>then created 5 isosurfaces (~7.4 million cells and ~3.7 points) and
>rendered it just fine.
>
>
>
>One last piece of advice: don't run D3 on your structured data.
>ParaView can balance your structured data without any help.  D3 is
>designed for unstructured data.  The first thing it will do is convert
>the structured data to unstructured, which is a much less efficient
>representation.  It makes more sense to run D3 on the output of the
>contour filter, but that is probably not worthwhile unless the contour
>is very big and very unbalanced.
>
>
>
>-Ken
>
>
>
>   _____
>
> From: paraview-bounces+kmorel=sandia.gov at paraview.org
>[mailto:paraview-bounces+kmorel=sandia.gov at paraview.org] On Behalf Of
>Raashid Baig
>Sent: Thursday, July 05, 2007 12:25 PM
>To: paraview at paraview.org
>Subject: [Paraview] Newbie question about paraview's parallel
>visualization procedure
>
>
>
>I am a newbie to parallel visualization and ParaView in general, I
>have some doubts which may be very fundamental.
>
>I am using ParaView2.6.X and trying to do some performance analysis
>and dataset limit of ParaView in general as a part of an academic
>project. I want to see what are the gains in CPU & memory usage and
>time required to render a particular dataset when ParaView is run in
>parallel. All machines are Intel Core Duo 2, 2GB DDR2 RAM, and 2GB
>swap, all machines have NVidia 7series graphics cards and have
>Debian/Ubuntu Linux
>
>I have structured data-sets with point attributes in form of VTK
>legacy files.  When I run paraview in stand-alone mode on a single
>machine, I am able to draw 5 iso-surface for structured grid datasets
>upto 5 million points. But when I put the same VTK legacy files on 3
>different computers (all have ParaView 2.6.X installed) and run
>ParaView through LAM/MPI in distributed stand alone mode (as described
>in the ParaView book) on these 3 machines, the performance decreases
>for the isosurface case. Not only does the time taken to render final
>image, cpu/memory usage increase, I am only able to visualize till 1
>million grid points. After 1 million point the get an error (this
>particular error is for a dataset of 2 million) :
>
>raashid at ged:~/src/cvs/paraview-unix/bin$ mpirun -np 3 -x
>DISPLAY=10.101.11.71:0.0 ./paraview
>ErrorMessage
># Error or warning: There was a VTK Error in file:
>/home/raashid/src/cvs/ParaView/VTK/Common/vtkDataArrayTemplate.txx (266)
>vtkIdTypeArray (0xe041768): Unable to allocate 59135376 elements of size
>4 bytes.
>ErrorMessage end
>------------------------------------------------------------------------
>-----
>One of the processes started by mpirun has exited with a nonzero exit
>code.  This typically indicates that the process finished in error.
>If your process did not finish in error, be sure to include a "return
>0" or "exit(0)" in your C code before exiting the application.
>
>PID 16283 failed on node n0 (10.101.11.71) due to signal 11.
>------------------------------------------------------------------------
>-----
>
>I get the same error as above if I use a D3 filter before applying the
>iso-contour.
>
>
>Following the ideas of a technical report I tried to open the VTK
>legacy file when ParaView server was running on 3 different computers
>and the client was running on a different computer, apply the D3
>filter and then save the file as PVTK unstructured grid format
>(*.pvtu, with 1 ghost levels), close the paraview, start a fresh
>paraview session with the same configuration (ParaView server was
>running on 3 different computers and the client was running on a
>different computer) load the master *.pvtu file and do the same
>iso-contour example as above, the server again crashes and displays
>the following error.(this particular error is for 2.5 million grid
>points)
>
>On the server side I get the message :
>------------------------------------------------------------------------
>------
>raashid at ender:~/src/cvs/paraview-unix/bin$ mpirun -np 3 -x
>DISPLAY=10.101.11.71:0.0 ./pvserver
>Listen on port: 11111
>Waiting for client...
>Client connected.
>Process id: 0 >> ERROR: In
>/home/raashid/src/cvs/ParaView/VTK/Common/vtkDataArrayTemplate.txx, line
>95
>vtkIdTypeArray (0xd243258): Unable to allocate 75216436 elements of size
>4 bytes.
>
>Process id: 0 >> ERROR: In
>/home/raashid/src/cvs/ParaView/Servers/Common/vtkProcessModule.cxx, line
>1187
>vtkProcessModule (0xb395560): Exception: Insufficient memory exception.
>------------------------------------------------------------------------
>------
>
>On the client side I get the message
>------------------------------------------------------------------------
>-------
>raashid at ged:~/src/cvs/paraview-unix/bin$ ./pvclient
>--server-host=10.101.11.72
>Connected to server
>ErrorMessage
># Error or warning: There was a VTK Error in file:
>/home/raashid/src/cvs/ParaView/Servers/Common/vtkProcessModule.cxx
>(1171)
>vtkProcessModule (0xc0c7530): Received exception from server:
>Insufficient memory exception.
>ErrorMessage end
>ErrorMessage
># Error or warning: There was a VTK Error in file:
>/home/raashid/src/cvs/ParaView/Servers/Common/vtkServerConnection.cxx
>(67)
>vtkServerConnection (0xc0ee1b8): Server Connection Closed!
>ErrorMessage end
>------------------------------------------------------------------------
>--------
>
>Am I using the wrong file type, if yes what should I use ?
>Is there some threshold limit I am violating ?
>
>Please help me with this problem, because I am in serious trouble.
>
>
>
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