VMD-L Mailing List

From: lam nguyen (lamvn08_at_gmail.com)
Date: Fri Nov 18 2011 - 13:42:12 CST

Strangely I got a temporary solution to the freezing-while-rotating
problem: right-click on the VMD window. Anyway, it's much less annoying now
with that solution.

Lam

On Fri, Nov 18, 2011 at 10:43 AM, lam nguyen <lamvn08_at_gmail.com> wrote:

> Thanks John,
>
> By doing what you suggested, the memory is improved a lot even though VMD
> still shows MSAA(16). It's great that now I can open many windows.
>
> However there is still another problem that I did not mention previously.
> When I rotate the object in VMD, the window freezes after few moves without
> affecting other programs. I would have to click at another window - any
> window, to "activate" the VMD window again. But the problem persists. I
> have to keep on clicking at another windows to be able to rotate the object
> to the viewing angle I want.
>
> This seems a strange behavior. Anyone has experienced this?
>
> Lam
>
>
> On Fri, Nov 18, 2011 at 9:18 AM, John Stone <johns_at_ks.uiuc.edu> wrote:
>
>> Lam,
>> Okay, I see one thing that may explain the memory use issue you're
>> having:
>>
>> On Thu, Nov 17, 2011 at 12:20:41PM -0800, lam nguyen wrote:
>> [...]
>> > Info) OpenGL renderer: Quadro FX 580/PCI/SSE2
>> > Info) Features: STENCIL MSAA(16) MDE CVA MTX NPOT PP PS GLSL(OVF)
>>
>> The MSAA(16) indicates that your display driver is using 16 antialiasing
>> samples per pixel in the VMD OpenGL window. This is 4 times higher than is
>> normally used, and for each sample more GPU memory is used...
>>
>> I would suggest that you try force-disabling multisample antialiasing
>> on your GPU and see if the memory usage is significantly decreased.
>> You should be able to do this using a command like the ones at the
>> top of this NVIDIA documentation page:
>>
>> http://us.download.nvidia.com/XFree86/Linux-x86_64/285.05.09/README/openglenvvariables.html
>>
>> Try this:
>> nvidia-settings --assign FSAA=0 --assign FSAAAppControlled=0 --assign
>> FSAAAppEnhanced=0
>>
>> If you set that and then re-run VMD, how does it affect your GPU memory
>> use?
>>
>> To revert to your previous antialiasing setting, do this:
>> nvidia-settings --assign FSAA=5 --assign FSAAAppControlled=1 --assign
>> FSAAAppEnhanced=0
>>
>> To set it for something that's a potential compromise, try this:
>> nvidia-settings --assign FSAA=5 --assign FSAAAppControlled=0 --assign
>> FSAAAppEnhanced=1
>>
>> Cheers,
>> John Stone
>> vmd_at_ks.uiuc.edu
>>
>> --
>> NIH Resource for Macromolecular Modeling and Bioinformatics
>> Beckman Institute for Advanced Science and Technology
>> University of Illinois, 405 N. Mathews Ave, Urbana, IL 61801
>> http://www.ks.uiuc.edu/~johns/ Phone: 217-244-3349
>> http://www.ks.uiuc.edu/Research/vmd/ Fax: 217-244-6078
>>
>
>