[rheringer]

Hi all,

We intend to install a new CFD lab for didactic purposes. We think that a server(s)/(30)clients configuration may be a better solution (maintenance in mind).
The clients will be minimal terminals with some graphical capabilities while the server take the hard processing work (as server/client should be).

The question: THIN CLIENTS could be used as client terminals in this case (numerical simulation, visualization)?

Any suggestion will be appreciated.

Thanks all,

rheringer

[wyldckat]

Greetings rheringer,

It's theoretically possible, but:

• The server will need to be properly prepared with some seriously powerful graphics card(s). Professional graphic cards in fact, since these are more oriented for engineering/rendering purposes.
• It will depend on the CFD+pre/post-Processing software you are planning to use. For a post-processing example: ParaView can use the remote server's graphics cards as rendering farms: http://www.paraview.org/Wiki/Setting..._GPUs_Per_Node

I would advise you to first test this theory with a high end PC acting as a server and a low end PC/laptop as the client. An old Pentium 4 1.x GHz as client vs i7 920 workstation acting as server (or respective AMD counterparts), would be a nice test pair. Also, it will seriously depend on the CFD software you are using, since it will depend on whether a functionality similar to ParaView is supported or not.

Of course that if you're trying to save some cash with this set-up, than the server should use a free Linux distribution

Another thing you should take into account is what type of thin-client you are planning to use, or more importantly, if you're going to use Atom based clients or ARM based clients (I'm talking about their CPU ). ARM based clients in CFD is something I'm not familiar with, but at least ParaView should work well with them, which is something I think can't be said for commercial CFD applications...

Best regards,
Bruno

[rheringer]

Thank you Bruno, for your answer.

I think we chose a good video card for the server (nVidia QUADRO FX4800). But, an ordinary video card (even on-board) installed in each terminal couldn't make this work? (cfd post-processing in college course level)
I mean, couldn't the graphical acceleration be processed in the client terminal?

The system we have in mind is:

- Software (open source) -
OS: Ubuntu GNU/Linux or another convenient linux distribution
CFD package: OpenFOAM (1st option)
Visualization: Paraview

- Hardware (server) -
CPU: 2 Processors Intel Xeon X5690 HT - 6x 3.46GHz, TDP 130w, Cache 12MB
Mobo: Intel Workstation Board Dual Xeon, Modelo S5520SC
Chipset: Intel S5520 (Tylersburg)
RAM: 48 GB
SSD: 120 GB X25-M Intel SSDSA2MH120G2K5
Hard Disk: 2 TB SATA3Gb/s, Seagate Barracuda LP, Cache 32MB
Video: PNY nVidia QUADRO FX4800, 1.5 GB

Best regard,

Romulo

[7islands]

Hi Romulo, I've been teaching CFD and stress analyses for several years in an undergraduate course of around 45 students. Our system is:

Thin clients:
Celeron 2.8 GHz (cutdown version of Pentium4), 1GB RAM, integrated Intel graphics
Windows XP Professional
OpenFOAM 1.4 for Cygwin, Gmsh 2.0.8, ParaView 3.4 (the software are more or less customized to suit the system and to meet our specific needs)

Server:
Hardware unknown, houses boot image of the thin clients, provides disk space of 120 MBytes(!) per student

The hardware are becoming outdated (> 5 years old) but even with the system we are barely able to run cases of around OpenFOAM tutorial sizes (~30 000 cells) and pre/post-processings on the thin clients.

The optimal hardware/software configuration quite depends on what you plan to do, but in any case, I would say that what really count are good teaching assistants...!

Takuya

[rheringer]

Hi Takuya,

Thank you for sharing your experience with us.
The system we are looking for seems quite similar to your lab (hardware/software).
It's useful to known this config work well somewhere.

Maybe the real challenge will be take all the software working fine on the server/terminals, instead the particular hardware used...

Do you think some linux distribution could be easily used in your case, instead Windows XP with Cygwin?

Romulo

[7islands]

Hi,

Originally Posted by rheringer

Maybe the real challenge will be take all the software working fine on the server/terminals, instead the particular hardware used...

Indeed, I did careful software customizations and testings which worked out fine. However our unexpected and biggest problem was not the processor/graphics performance but bandwidth contention to network storage when all students do the same operation involving disk reading/writing following the instructor. I would advise rigorous network storage testing if you consider one.

Do you think some linux distribution could be easily used in your case, instead Windows XP with Cygwin?

The clients use Windows because the system is shared with other courses in our faculty, such as C/Java programming, embedded microcontroller programming or even the usual Word/Excel courses. I had no choice but Windows since the system was already there when I started the course... I would have definitely used Linux if the system was dedicated.

Takuya

[rheringer]

Originally Posted by 7islands

... However our unexpected and biggest problem was not the processor/graphics performance but bandwidth contention to network storage when all students do the same operation involving disk reading/writing following the instructor. I would advise rigorous network storage testing if you consider one.
...
Takuya

Good tip. I'll take this into account.

Thanks again,

Romulo

[rheringer]

Unfortunately we could not make conclusive tests with thin client / server (as proposed by Bruno). Thus, we chose a solution similar to that of Takuya (above).
However, if anyone knows a successful solution using (real) thin clients, please let us know.

Thank you both.

Romulo

[wyldckat]

Hi Romulo,

I haven't gotten my hands on a little thin client yet, but I did test yesterday a very sweet innate ability that ParaView has: I used a ParaView 3.8.0 32bit on Windows to connect to a 64 bit 3.8.0 ParaView server (pvserver) running on Linux!
Unfortunately, I didn't have time to do some serious testing, but at least it connected very well and I could even browse the remote folders from within my local ParaView!

If I get another chance to do some tests, I'll write about it here

By the way, if this works well, it's not very difficult to imagine users using terminal windows to access remotely their areas in the server to edit their OpenFOAM cases, running them and then plugging into their own session of pvserver from their ParaView client!

Best regards,
Bruno