[Paraview] Rendering in parallel

[Moreland, Kenneth]

OK, I can see where things are going majorly wrong here. Let's start with the worst of the problems.

I notice on the bottom of your screenshot that your desktop has 4 windows named ParaView Server #0, ParaView Server #1, etc. Those are X windows that the server is opening up on your desktop. You really don't want the server to do that. Those windows are used for OpenGL rendering. If they are opened on your desktop, that means that all four of those processes on your server are sending all the geometry to your desktop, your desktop renders all the geometry, and then the images get shipped to the server. The server then composites those images together and sends the result back to your desktop.

I'm sure that when you are running the server, your DISPLAY environment variable is pointing back to your desktop, which is causing the problem. You need to make sure the server is run with display set to localhost:0. More information is on the ParaView wiki at:

http://www.paraview.org/Wiki/Setting_up_a_ParaView_Server#X_Connections

That said, I'm not sure using your server is going to give you a big rendering performance boost over your desktop. The parallel rendering is really designed for large clusters with many GPUs. The rendering should work OK on your desktop as long as you're not thrashing your virtual memory (which is possible).

-Ken

From: Jérémy Santina <jeremy.santina at gmail.com<mailto:jeremy.santina at gmail.com>>
Date: Wednesday, July 2, 2014 4:17 AM
To: Kenneth Moreland <kmorel at sandia.gov<mailto:kmorel at sandia.gov>>
Cc: "paraview at paraview.org<mailto:paraview at paraview.org>" <paraview at paraview.org<mailto:paraview at paraview.org>>
Subject: [EXTERNAL] Re: [Paraview] Rendering in parallel

Sorry for my poor description. I will try to give more information.

I am loading a Multi-block Dataset without applying any filters and the rendering is surface rendering. In order to understand how it works, I am just running a pvserver in parallel on another computer (with a better GPU) connected via SSH. The graphics card is an NVIDIA Quadro FX 4600 and you have to know that I am not alone using this machine.  Server and client both work on Linux. So would the problem be because there is only one GPU ?

I join a picture with this message.

I would have another question. When I launch the rendering in parallel, a variable called vtkProcessId is generated. What is it ? Does it do the same thing if I apply Process Id Scalars filter ? Or are they two different things ?

Jérémy


2014-07-01 18:08 GMT+02:00 Moreland, Kenneth <kmorel at sandia.gov<mailto:kmorel at sandia.gov>>:
To check the distribution of the data, use the Process Id Scalars filters. That should color the data based on which processor it is located.

It might help if you described your system more completely. What kind of data are you loading? Is it image data? Polygon data? AMR? An unstructured grid? Are you applying any filters? How are you rendering it? Is it surface or volume rendering? Is there any transparency? Can you send a picture? What kind of parallel computer are you using? Are you running ParaView on your desktop in multi-core mode (I think rendering actually serializes in that case because you still have only one GPU.), or are you connecting to a cluster? How many nodes on your cluster and how are they configured?

-Ken

From: Jérémy Santina <jeremy.santina at gmail.com<mailto:jeremy.santina at gmail.com>>
Date: Tuesday, July 1, 2014 2:31 AM
To: Kenneth Moreland <kmorel at sandia.gov<mailto:kmorel at sandia.gov>>
Cc: "paraview at paraview.org<mailto:paraview at paraview.org>" <paraview at paraview.org<mailto:paraview at paraview.org>>
Subject: [EXTERNAL] Re: [Paraview] Rendering in parallel

Actually, I did try the D3 filter but I didn't really see any better results. Maybe it is because I don't know how to configure it. How does D3 filter work ?



2014-06-30 16:21 GMT+02:00 Moreland, Kenneth <kmorel at sandia.gov<mailto:kmorel at sandia.gov>>:
Jeremy,

Like the other parallel processing in ParaView, the efficiency is dictated by the distribution of the data. If your data distribution is highly imbalanced such as when all the data is on one process as in your case, then all the processing will happen where the data is and the rest of the processors will remain idle.

You could try running the D3 filter. That should redistribute the point data more evenly.

-Ken

From: Jérémy Santina <jeremy.santina at gmail.com<mailto:jeremy.santina at gmail.com>>
Date: Monday, June 30, 2014 2:55 AM
To: "paraview at paraview.org<mailto:paraview at paraview.org>" <paraview at paraview.org<mailto:paraview at paraview.org>>
Subject: [EXTERNAL] [Paraview] Rendering in parallel

Good morning,

I am a novice user of Paraview and there are some aspects which I am not familiar with. Here is one of the issues I am having :

I run Paraview in Client-Server mode, performing the data processing and the rendering on the remote server, and I read a Tecplot Binary File (.plt) composed of more than 30 millions of points. This take a lot of time. An idea to speed up the calculation is to launch the server in parallel. I know that many readers can not read in parallel (it is the case of TecplotBinaryFileReader I think) so I don't expect any improvment in this way.

But, examining the Timer Log, I noticed that it doesn't speed up the rendering either. I tested many times displaying the points and both experiment with parallelism and without gave the same results (about 40-50 sec). I don't understand why.

Do I misinterpret the Timer Log ? Is the time of rendering long enough to conclude ? Do I have to set specific parameters to make it works ?

I thank you in advance for your help.

Jérémy


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://public.kitware.com/pipermail/paraview/attachments/20140702/7ad5fa71/attachment-0001.html>