On 10/31/18 10:47 AM, Ramon Guixà wrote:
Hi Justin, I do not have access to GPUs with ECC, but I have actually run the same tpr in different machines with different GPUs, including GTX 980, 1060 and 1080. In all cases, I get the same problem. Although they are all non-ECC cards, it is quite unlikely that a bit flip is behind this, isn't it?
Certainly is. It wasn't clear if you were just running over and over again on the same card or what.
In fact, I had simulated before CHARMM-GUI systems using GTX cards and never had a problem. Since this has only benn happening recently to me, so I am wondering if I should blame the new force field (CHARMM36m) or whether CHARMM-GUI changed something in the way they generate gromacs topologies?
I sincerely doubt it's the force field. We validate that extensively across many compounds to verify that GROMACS and CHARMM compute the forces the same (I do this myself when we produce a new force field port). We don't (can't) do that easily on GPU, but if the forces are different, that points to a software bug, because everything about the CPU implementations is identical. Given that you have a sudden change in system behavior, that further points to a software bug, in my opinion, because if something was fundamentally wrong with the force field, (1) you would see it on CPU runs and (2) it would almost certainly occur much earlier in the simulation.
-Justin -- ================================================== Justin A. Lemkul, Ph.D. Assistant Professor Virginia Tech Department of Biochemistry 303 Engel Hall 340 West Campus Dr. Blacksburg, VA 24061 jalem...@vt.edu | (540) 231-3129 http://www.thelemkullab.com ================================================== -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.
