Re: "Periodic cell has become too small for original patch grid!" with membrane system on GPU

From: David Hardy (dhardy_at_ks.uiuc.edu)
Date: Fri Aug 25 2017 - 14:39:24 CDT

Dear Gleb,

I've found and fixed a long-standing bug in the NAMD 2.12 CUDA kernels that may have affected your simulation. You might want to try the NAMD nightly build from http://www.ks.uiuc.edu/Development/Download/download.cgi?PackageName=NAMD <http://www.ks.uiuc.edu/Development/Download/download.cgi?PackageName=NAMD> to see if you are able to run on your GPU.

Best regards,
Dave

--
David J. Hardy, Ph.D.
Theoretical and Computational Biophysics
Beckman Institute, University of Illinois
dhardy_at_ks.uiuc.edu
http://www.ks.uiuc.edu/~dhardy/
> On Jul 20, 2017, at 6:03 AM, James Starlight <jmsstarlight_at_gmail.com> wrote:
> 
> Dear NAMD Users!
> 
> I have faced with a following problem running the lattest NAMD with
> GPU quadro 5000k. I am dealing with the GPCR-membrane system
> assembling with the CHARM-GUI with all input conf files provided on
> the default.
> 
> I took the system just after the equilibration and running it with the
> CHARM-GUI parameters obtained the following error:
> 
> FATAL ERROR: Periodic cell has become too small for original patch grid!
> Possible solutions are to restart from a recent checkpoint,
> increase margin, or disable useFlexibleCell for liquid simulation.
> 
> because this is a membrane-consisting system and disable
> useFlexibleCell is not possible I try  to increase margin up to 5.0,
> obtaining another error:
> 
> FATAL ERROR: High global CUDA exclusion count!  (96033 vs 92328)
> System unstable or pairlistdist or cutoff too close to periodic cell
> size.
> 
> There was no such error with this system running on CPU cluster. How I
> should modify conf file to solve the issue?
> 
> Thanks!
> 
> Gleb

This archive was generated by hypermail 2.1.6 : Mon Dec 31 2018 - 23:20:32 CST