Hi, Is this rather large box a system that can actually be simulated with a useful speed on a single Fermi GPU? Even with 5 fs time-step you won't get much more than 1-1.5 ns/day on a fast Fermi GPU like a GTX 580.
Given that you are quite a bit above the limit, unless you are using a quite large nstlist, you may not be able to decrease it enough to fit the system on the GPU. What you can do instead is to use domain-decomposition and start multiple ranks per GPU. In your case two-way DD should be enough. Cheers, -- Szilárd On Fri, Sep 5, 2014 at 11:24 PM, Mirco Wahab <mirco.wa...@chemie.tu-freiberg.de> wrote: > I've run into a problem with an older card (GTX-580) > which is CC 2.0. On a larger box size, mdrun stops > with: > > Fatal error: > Watch out, the input system is too large to simulate! > The number of nonbonded work units (=number of super-clusters) > exceeds themaximum grid size in x dimension (86276 > 65535)! > > > This seems to refer to the CUDA "grid of thread blocks per dimension", > limitation specific for CC below 3.0 (I know this system worked already > on a CC 3.0 device). > > My question: can this grid count calculated by mdrun be "manipulated" > somehow by mdp options (nstlist, rvdw, rlist)? > > Thanks, > > M. > -- > 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. -- 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.