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calim_cfd May 4, 2012 09:34

wrappers_memory_display
 
Hellos ccm+users!

I'm rather new to ccm and its wrapper tools. I'm a OF user and im used to SHM, which is similar to the trimmer wrapper in ccm.

I have some questions about memory management in ccm:

1) im working on a deskop with suse64bit 1 quad xeon and 24gb and i got a server to which i submit part of the model. I'm working with unclean geometries and i gotta use wrappers. But in ccm depending on what you do the system consumes the whole amount of physical memory and all of a suddem u cant even wrap simple geometries. I noticed that if you use wrapper you may remain with lots of "used but idle gbs" and i gotta restart the file to reset the memory.. does anybody know what command in ccm responsible for it? any work arounds? what to avoid?

plus how big can my model be, with my machine, if i need to user wrapper, remesher and say poly (which is more memory consuming)..?

2)what's the deal with the display in ccm? i gotta a mid-range fx quadro 1800 (at least got check the machine). i shouldnt stumble into <1fps that often. I checked the options>vizuali.> and i changed the fps to 20 (from 1) and it appears to increase the display speed... should i increase it even more (im not on my desktop now) or was it a coincidence?

Thanks a lot to any1 who can give me some hints on how to avoid swaping my hardrivers.. :D:D:D

tyty

abdul099 May 6, 2012 08:58

1. I'm not sure, but I think, CCM+ keeps all representations in the memory. So when you mesh your geometry, it keeps the initial surface. When you volume mesh your surface and have finished, it will still keep the remeshed surface in the memory rather than deleting it and just keeping it on the harddrive. But it doesn't load it from the harddrive as long as you don't need it.
That might be a reason why it takes a lot of memory. My only hint to avoid that is to save the file, close it and open it again.
As I said, I'm not fully sure about this. Maybe you'll get a more founded information when contacting the support.

I can't make any statement about the model size you can handle with your machine. There is a rule saying 1 million poly cells takes about 1GB memory (the same ish for meshing and solving) and I can confirm that from my own experience.
But the surface wrapper can take a considerable amount of memory as well. How much depends on your geometry, your mesh settings etc, but usually it's a lot.

2. The display is not very fast in ccm+ (some say, it's horrible slow). But it depends a lot on your environment. On my Linux workstation the display is much slower than on my windows desktop, although the graphics card of the workstation should be nearly as powerful. If you can, play around with the graphics card drivers. Some offer a better performance, and that doesn't necessarily needs to be the newest one. But you shouldn't expect any miracles...

calim_cfd May 6, 2012 10:19

Hi abdul! thanks for replying!

that display thing i wrote about..have you tried? increasing the fps of your refresh rate? it seems to improve the display fps.. ill make further tests in the morning..

about the memory.. the representations might be the issue... but i was working on the same geometry and everything was fine.. but when i switched on remesher and started using other wrapping options, like the gap one, or even changing the sizes slightly i was unable to mesh the same geo .. then i reset the memory and i removed the other options like the gap one, the remesher but nothing.. the software seemed to have flagged the file somehow to use all the memory he could get lol... and i was unable even to get a very coarse wrapped surface from the same initial surface i'll try a new file tomorrow and c what happens..

thanks for the input

ps: nice sign:D

xamo May 15, 2012 08:46

Hi,

UserGuide:

Increase the Refresh Rate property. This will cause surfaces to be demoted to a simpler representation (and hence drawn faster) when interaction occurs in the scene.


Regards

xamo

calim_cfd May 15, 2012 17:39

thanks for confirming pointing that out... :)

im getting the hang of this software already :cool:

thx again


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