Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
Long delays opening mph files in COMSOL4.0?
Posted 09.07.2010, 16:21 GMT-4 General 9 Replies
Please login with a confirmed email address before reporting spam
The mph files in question are simple 2-D Rayleigh-Benard convection benchmarks that use the Laminar Flow (spf) and Heat Transfer (ht) modules in COMSOL Multiphysics. I have run these benchmarks using COMSOL3.5a in the past without any difficulty, and I recreated them from scratch in COMSOL4.0. The oddest thing is that once an mph file has been opened successfully, other mph files can be accessed from the File menu and they load very quickly. It only seems to happen with the first model file opened in a given COMSOL session.
I have encountered this problem on several machines, all dual quad-core MacPros running either OSX 10.6.3 or 10.6.4, with anywhere from 8 - 16 Gb of RAM, so I don't think hardware is the problem. The problem occurs with both COMSOL4.0 and 4.0a, but not with COMSOL3.5a. Has anyone else experienced this? Any thoughts as to the root cause or a possible solution would be appreciated.
Thanks!
Paul
Please login with a confirmed email address before reporting spam
in the pre 4.0a I have also noted long delays, it was mostly related to the java loading of the help files, so my rule was:
a) always close the dynamic help window before saving any file and closing COMSOL
b) in V4.0a there is an check option to not load by default the help files in the Preferences
Sometimes, it did also help to remove the /.comsol/v40 user directory, but then you delete your default settings and you must redefine them (rather quickly done anyhow)
hope this helps
Ivar
Please login with a confirmed email address before reporting spam
Having played with things a little more, I believe it may be related to the physical dimension of the model geometry. I just experimented with creating a simple square model geometry (w/o a mesh, just the geometry). For squares with sides < ~1e4 meters there is no perceptible delay in opening the file. At lengths of ~1e+5 meters a short delay (10s of seconds) is evident. At lengths of ~1e+6 m the delay is fairly pronounced (several minutes).
I study convection in the Earth's upper mantle, and relevant length scales for my models are on the order of ~1e+6 meters. I'm guessing this is the source of the problem.
Paul
Please login with a confirmed email address before reporting spam
That is funny, are you using the scale factor for the geometry ? In anycase these are typically the type issues I report to support so they can take a look, you should do the same I believe, they are helpful.
I just made a cube of 1e6m with 4.0.0.982 v4.0a no particular delay, but I only meshed it with "normal", and without scaling to anything else than default [m]
Good Luck
Ivar
Please login with a confirmed email address before reporting spam
Paul
Please login with a confirmed email address before reporting spam
That is also possible, I'm on holiday so that means Vista-32, for the time being ;)
Ivar
Please login with a confirmed email address before reporting spam
The delay in opening files is unaccetably long.
Please login with a confirmed email address before reporting spam
"To get around the problem you can switch 2D renderer.
1) Open the Preferences dialog box from the Options menu.
2) Select "Graphics" in the list to the left.
3) Change "2D rendering" to "Swing".
The SWT renderer has a problem when changing the scale of the graphics.
When you start the scale is ~1. When you open a model with a scale of 1e6
you get the delay when changing scale. But if you would zoom out the 2D
graphics area to about 1e6 before opening the model there is no delay.
The Swing renderer does not have this delay problem, and we hope to fix
the SWT renderer in COMSOL 4.1."
I have tried this suggested solution and it does, in fact, do the trick.
Cheers,
Paul
Please login with a confirmed email address before reporting spam
I am experiencing this problem too. I have comsol 4.1 installed on both Ubuntu 10.04 64-bit and Windows 7 64-bit, and am running RF module in-plane propagation problems with ~500k DOFs. My simulation domain is a few tens of microns, and the geometry scale is in microns. I have tried setting the 2D rendering to Swing and SWT. Still it takes around 30 minutes sometimes to reinitialise the GUI on both systems.
Also, after running a model, it tends to hang for a couple of minutes after clicking on a plot menu before allowing to me plot any results.
If anyone knows how I can fix this problem then please enlighten me.
Please login with a confirmed email address before reporting spam
it could come from the geometry, if it is very long and complex. Try to switch to a CAD kernel and not the default COMSOL one. There is an issue discussing this in one of the KB i Believe.
be patient, it will finally get out and then change the geometry kernel selection
--
Good luck
Ivar
Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.
