From: John Stone (johns_at_ks.uiuc.edu)
Date: Thu Feb 12 2015 - 09:15:59 CST

Norman,
  How much video memory does your GPU have?
What else are you running on the machine at the time that this
error occurs? (for example, is Google Chrome running? Other
instances of VMD? Anything else that uses the GPU at all?)

Cheers,
  John

On Thu, Feb 12, 2015 at 09:44:34AM +0100, Norman Geist wrote:
> Hey John,
>
> the exact error message is:
>
> ERROR) OptiXRenderer) ERROR: Unknown error (Details: Function "RTresult
> _rtContextLaunch2D(RTcontext, unsigned int, RTsize, RTsize)" caught
> exception: (bvhtools error)An unexpected memory allocation error occurred in
> TrivialThrustAllocator, [21823538], [15270173]) (OptiXRenderer.C:1188
>
> GPU is a Geforce GTX660 (propritary NVidia driver version: 343.22)
>
> This error occurs for me doing the following steps:
>
> 1. open a fresh vmd
> 2. disable axis
> 3. enable ruler in scale mode
> 4. render using TachyonOptix (interactive or not)
>
> Norman Geist.
>
> > -----Original Message-----
> > From: John Stone [mailto:johns_at_ks.uiuc.edu]
> > Sent: Wednesday, February 11, 2015 5:21 PM
> > To: Norman Geist
> > Cc: 'Tristan Croll'; VMD Mailing List
> > Subject: Re: vmd-l: Handful of rendering issues
> >
> > Norman,
> >
> > On Wed, Feb 11, 2015 at 04:32:35PM +0100, Norman Geist wrote:
> > > 1. Using the "ruler" in "scale" mode, when nothing else
> > (including
> > > axis) is visible, TachyonOptix will crash.
> >
> > I don't get a crash when I do this on my system here, but I will
> > say that the rendering of the scale bar is pretty wacky due to
> > weaknesses in the scheme I used for setting cylinder radii for OptiX
> > when drawing lines in VMD 1.9.2, something that still needs more work.
> > Can you post the error message that VMD prints?
> > Without the error it's hard to say what's going on there for you.
> >
> > > 2. The general fact TachyonOptix will no more work without
> > > restarting VMD, if it has crashed once.
> >
> > It depends. If the OptiX runtime runs out of GPU memory or other
> > scenarios that it can't bail out of, it will terminate rendering and
> > usually destroy the OptiX context on its way down. In some of these
> > cases,
> > the state of the CUDA context also gets destroyed, and VMD is not able
> > to
> > recover it. There are also a lot of cases where VMD does recover from
> > less serious issues, but unfortunately, I'd say that running the GPU
> > out
> > of memory is one of the more common problems, particularly on a machine
> > where other graphical apps are competing for resources (e.g. Google
> > Chrome,
> > a surprisingly resource hungry application, in terms of GPU memory...)
> >
> > Cheers,
> > John
> >
> >
> > > Norman Geist.
> > >
> > >
> > >
> > > From: owner-vmd-l_at_ks.uiuc.edu [mailto:owner-vmd-l_at_ks.uiuc.edu] On
> > Behalf
> > > Of Tristan Croll
> > > Sent: Wednesday, February 11, 2015 12:15 PM
> > > To: vmd-l_at_ks.uiuc.edu
> > > Subject: vmd-l: Handful of rendering issues
> > >
> > >
> > >
> > > Hi there,
> > >
> > >
> > >
> > > I have a few minor rendering-related issues/suggestions in VMD
> > 1.9.2:
> > >
> > >
> > >
> > > - If I have an isosurface visualised in the default point
> > representation
> > > and switch to GLSL rendermode, every point becomes a VERY large
> > sphere and
> > > the system slows to a crawl.
> > >
> > >
> > >
> > > - When a wireframe is rendered in Tachyon the lines are of course
> > replaced
> > > by thin cylinders. This works out nicely in the CPU-only Tachyon
> > > (particularly if I use a transparent material, yielding a nicely
> > > unobtrusive mesh), but the cylinder diameter is much larger in
> > > Tachyon-OptiX. Is it possible to shrink this, or is this one of
> > the
> > > trade-offs that allows the renderer to be so blazingly fast?
> > >
> > >
> > >
> > > - When using the interactive renderer, closing the rendering
> > window with
> > > the mouse rather than pressing Esc or q crashes VMD.
> > >
> > >
> > >
> > > - I think it would be awesome if the interactive renderer had an
> > option to
> > > render the scene at some multiple of the screen resolution, for
> > when
> > > poster-quality images are needed.
> > >
> > >
> > >
> > > Cheers,
> > >
> > >
> > >
> > > Tristan
> > >
> > >
> >
> > --
> > NIH Center 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/

-- 
NIH Center 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/